From dea6ef2031b6c76a7a52341a852c5e4b8504ac2a Mon Sep 17 00:00:00 2001
From: GitHub Actions <actions@github.com>
Date: Tue, 5 Mar 2024 00:42:49 +0000
Subject: [PATCH] site deploy

Auto-generated via {sandpaper}
Source  : 2d8fb43757814d486a3114bda9a310f510d3e031
Branch  : md-outputs
Author  : GitHub Actions <actions@github.com>
Time    : 2024-03-05 00:42:32 +0000
Message : markdown source builds

Auto-generated via {sandpaper}
Source  : 13938776a3c177bd23753a47d1d11d1d65cd41e0
Branch  : l10n_main
Author  : Toby Hodges <tbyhdgs@gmail.com>
Time    : 2024-02-20 11:33:21 +0000
Message : New translations 01-intro.md (Japanese)
---
 01-intro.html                    |   17 +-
 02-filedir.html                  |  151 ++--
 03-create.html                   |  343 +++++----
 04-pipefilter.html               |   95 ++-
 05-loop.html                     |  292 ++++----
 06-script.html                   |  172 +++--
 07-find.html                     |   97 ++-
 404.html                         |    4 +-
 CODE_OF_CONDUCT.html             |    2 +-
 LICENSE.html                     |    2 +-
 aio.html                         | 1124 ++++++++++++++---------------
 discuss.html                     |    2 +-
 images.html                      |    4 +-
 index.html                       |   13 +-
 instructor-notes.html            |   14 +-
 instructor/01-intro.html         |   17 +-
 instructor/02-filedir.html       |  153 ++--
 instructor/03-create.html        |  345 +++++----
 instructor/04-pipefilter.html    |   95 ++-
 instructor/05-loop.html          |  292 ++++----
 instructor/06-script.html        |  172 +++--
 instructor/07-find.html          |   97 ++-
 instructor/404.html              |    4 +-
 instructor/CODE_OF_CONDUCT.html  |    2 +-
 instructor/LICENSE.html          |    2 +-
 instructor/aio.html              | 1128 +++++++++++++++---------------
 instructor/discuss.html          |    2 +-
 instructor/images.html           |    4 +-
 instructor/index.html            |   13 +-
 instructor/instructor-notes.html |   14 +-
 instructor/key-points.html       |    4 +-
 instructor/profiles.html         |    4 +-
 instructor/reference.html        |    2 +-
 key-points.html                  |    4 +-
 md5sum.txt                       |    2 +-
 pkgdown.yml                      |    4 +-
 profiles.html                    |    4 +-
 reference.html                   |    2 +-
 38 files changed, 2317 insertions(+), 2381 deletions(-)

diff --git a/01-intro.html b/01-intro.html
index 10521c767..d714aea2a 100644
--- a/01-intro.html
+++ b/01-intro.html
@@ -360,7 +360,7 @@ <h3 id="the-shell">The Shell<a class="anchor" aria-label="anchor" href="#the-she
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
 </div>
 <p>The shell typically uses <code>$</code> as the prompt, but may use a
 different symbol. In the examples for this lesson, we’ll show the prompt
@@ -380,7 +380,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
 </div>
 <p>The prompt might even include more than this. Do not worry if your
 prompt is not just a short <code>$</code>. This lesson does not depend
@@ -393,7 +393,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -401,20 +401,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="output" tabindex="0"><code>Desktop     Downloads   Movies      Pictures
 Documents   Library     Music       Public</code></pre>
 </div>
-<div id="command-not-found" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="command-not-found" class="callout-inner">
-<h3 class="callout-title">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="command-not-found">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a></h3>
 <div class="callout-content">
 <p>If the shell can’t find a program whose name is the command you
 typed, it will print an error message such as:</p>
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -540,7 +539,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/01-intro.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/02-filedir.html b/02-filedir.html
index 5af6d6f5e..0ab575f4f 100644
--- a/02-filedir.html
+++ b/02-filedir.html
@@ -331,7 +331,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -340,13 +340,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Here, the computer’s response is <code>/Users/nelle</code>, which is
 Nelle’s <strong>home directory</strong>:</p>
-<div id="home-directory-variation" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="home-directory-variation" class="callout-inner">
-<h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="home-directory-variation">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a></h3>
 <div class="callout-content">
 <p>The home directory path will look different on different operating
 systems. On Linux, it may look like <code>/home/nelle</code>, and on
@@ -385,13 +384,12 @@ <h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="
 first part of its name. Similarly, we know that <code>/Users</code> is
 stored inside the root directory <code>/</code> because its name begins
 with <code>/</code>.</p>
-<div id="slashes" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="slashes" class="callout-inner">
-<h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="slashes">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a></h3>
 <div class="callout-content">
 <p>Notice that there are two meanings for the <code>/</code> character.
 When it appears at the front of a file or directory name, it refers to
@@ -416,7 +414,7 @@ <h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#sl
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -441,7 +439,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -453,13 +451,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <strong>sub-directories</strong>. Any names in the output that don’t
 have a classification symbol are <strong>files</strong> in the current
 working directory.</p>
-<div id="clearing-your-terminal" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="clearing-your-terminal" class="callout-inner">
-<h3 class="callout-title">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="clearing-your-terminal">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a></h3>
 <div class="callout-content">
 <p>If your screen gets too cluttered, you can clear your terminal using
 the <code>clear</code> command. You can still access previous commands
@@ -479,23 +476,22 @@ <h3 id="getting-help">Getting help<a class="anchor" aria-label="anchor" href="#g
 </ol><div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <ol start="2" style="list-style-type: decimal"><li>We can read its manual with <code>man</code> (available on Linux and
 macOS):</li>
 </ol><div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>We’ll describe both ways next.</p>
-<div id="help-for-built-in-commands" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="help-for-built-in-commands" class="callout-inner">
-<h3 class="callout-title">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="help-for-built-in-commands">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a></h3>
 <div class="callout-content">
 <p>Some commands are built in to the Bash shell, rather than existing as
 separate programs on the filesystem. One example is the <code>cd</code>
@@ -514,7 +510,7 @@ <h4 id="the---help-option">The <code>--help</code> option<a class="anchor" aria-
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -545,20 +541,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   -F, --classify             append indicator (one of */=&gt;@|) to entries
 ...        ...        ...</code></pre>
 </div>
-<div id="unsupported-command-line-options" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="unsupported-command-line-options" class="callout-inner">
-<h3 class="callout-title">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="unsupported-command-line-options">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a></h3>
 <div class="callout-content">
 <p>If you try to use an option that is not supported, <code>ls</code>
 and other commands will usually print an error message similar to:</p>
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -576,7 +571,7 @@ <h4 id="the-man-command">The <code>man</code> command<a class="anchor" aria-labe
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>This command will turn your terminal into a page with a description
 of the <code>ls</code> command and its options.</p>
@@ -590,13 +585,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <kbd>Shift</kbd>+<kbd>N</kbd> (for moving backward).</p>
 <p>To <strong>quit</strong> the <code>man</code> pages, press
 <kbd>Q</kbd>.</p>
-<div id="manual-pages-on-the-web" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="manual-pages-on-the-web" class="callout-inner">
-<h3 class="callout-title">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="manual-pages-on-the-web">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a></h3>
 <div class="callout-content">
 <p>Of course, there is a third way to access help for commands:
 searching the internet via your web browser. When using internet search,
@@ -631,7 +625,7 @@ <h3 class="callout-title">Exploring More<code>ls</code>Options<a class="anchor"
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>-l</code> option makes <code>ls</code> use a
 <strong>l</strong>ong listing format, showing not only the
@@ -667,7 +661,7 @@ <h3 class="callout-title">Listing in Reverse Chronological Order<a class="anchor
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The most recently changed file is listed last when using
 <code>-rt</code>. This can be very useful for finding your most recent
@@ -691,7 +685,7 @@ <h3 id="exploring-other-directories">Exploring Other Directories<a class="anchor
 <div class="codewrapper sourceCode" id="cb14">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -722,7 +716,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
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@@ -744,9 +738,9 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
 </div>
 <p>These commands will move us from our home directory into our Desktop
 directory, then into the <code>shell-lesson-data</code> directory, then
@@ -763,7 +757,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -803,7 +797,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
 </div>
 <p><code>..</code> is a special directory name meaning “the directory
 containing this one”, or more succinctly, the <strong>parent</strong> of
@@ -813,7 +807,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -844,13 +838,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>Note that in most command line tools, multiple options can be
 combined with a single <code>-</code> and no spaces between the options;
 <code>ls -F -a</code> is equivalent to <code>ls -Fa</code>.</p>
-<div id="other-hidden-files" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-hidden-files" class="callout-inner">
-<h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-hidden-files">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a></h3>
 <div class="callout-content">
 <p>In addition to the hidden directories <code>..</code> and
 <code>.</code>, you may also see a file called
@@ -872,14 +865,14 @@ <h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
 </div>
 <p>How can you check what happened? <code>pwd</code> gives us the
 answer!</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
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@@ -896,7 +889,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
 </div>
 <p>Check that we’ve moved to the right place by running <code>pwd</code>
 and <code>ls -F</code>.</p>
@@ -922,7 +915,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
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@@ -932,17 +925,16 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Run <code>pwd</code> and <code>ls -F</code> to ensure that we’re in
 the directory we expect.</p>
-<div id="two-more-shortcuts" class="callout callout">
+<div id="callout8" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-more-shortcuts" class="callout-inner">
-<h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-more-shortcuts">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a></h3>
 <div class="callout-content">
 <p>The shell interprets a tilde (<code>~</code>) character at the start
 of a path to mean “the current user’s home directory”. For example, if
@@ -965,20 +957,20 @@ <h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Then <code>cd</code> into the <code>exercise-data/creatures</code>
 directory</p>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
 </div>
 <p>Now if you run</p>
 <div class="codewrapper sourceCode" id="cb39">
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
 </div>
 <p>you’ll see you’re back in <code>~/Desktop/shell-lesson-data</code>.
 Run <code>cd -</code> again and you’re back in
@@ -1014,7 +1006,7 @@ <h3 class="callout-title">Absolute vs Relative Paths<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>No: <code>.</code> stands for the current directory.</p></li>
 <li><p>No: <code>/</code> stands for the root directory.</p></li>
@@ -1055,7 +1047,7 @@ <h3 class="callout-title">Relative Path Resolution<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>No: there <em>is</em> a directory <code>backup</code> in
 <code>/Users</code>.</p></li>
@@ -1097,7 +1089,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>No: <code>pwd</code> is not the name of a directory.</p></li>
 <li><p>Yes: <code>ls</code> without directory argument lists files and
@@ -1117,7 +1109,7 @@ <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <figure><img src="fig/shell_command_syntax.svg" alt="General syntax of a shell command" class="figure mx-auto d-block"></figure><p><code>ls</code> is the <strong>command</strong>, with an
 <strong>option</strong> <code>-F</code> and an <strong>argument</strong>
@@ -1143,8 +1135,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
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@@ -1159,7 +1151,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1173,7 +1165,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
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 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1182,13 +1174,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 Library/              Users/
 Network/              Volumes/</code></pre>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout callout">
+<div id="callout9" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout-inner">
-<h3 class="callout-title">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="when-to-use-short-or-long-options">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a></h3>
 <div class="callout-content">
 <p>When options exist as both short and long options:</p>
 <ul><li>Use the short option when typing commands directly into the shell to
@@ -1218,7 +1209,7 @@ <h3 id="nelles-pipeline-organizing-files">Nelle’s Pipeline: Organizing Files<a
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>This command is a lot to type, but she can let the shell do most of
 the work through what is called <strong>tab completion</strong>. If she
@@ -1226,14 +1217,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
 </div>
 <p>and then presses <kbd>Tab</kbd> (the tab key on her keyboard), the
 shell automatically completes the directory name for her:</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>Pressing <kbd>Tab</kbd> again does nothing, since there are multiple
 possibilities; pressing <kbd>Tab</kbd> twice brings up a list of all the
@@ -1244,15 +1235,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb51">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
 </div>
 <p>To see all of those files, she can press <kbd>Tab</kbd> twice
 more.</p>
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
-<span id="cb52-2"><a href="#cb52-2" aria-hidden="true" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
+<span id="cb52-2"><a href="#cb52-2" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
 </div>
 <p>This is called <strong>tab completion</strong>, and we will see it in
 many other tools as we go on.</p>
@@ -1355,7 +1346,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/02-filedir.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/03-create.html b/03-create.html
index ba01b601b..eadd7aad1 100644
--- a/03-create.html
+++ b/03-create.html
@@ -323,7 +323,7 @@ <h3 id="step-one-see-where-we-are-and-what-we-already-have">Step one: see where
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -335,8 +335,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -351,7 +351,7 @@ <h3 id="create-a-directory">Create a directory<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
 </div>
 <p>As you might guess from its name, <code>mkdir</code> means ‘make
 directory’. Since <code>thesis</code> is a relative path (i.e., does not
@@ -360,7 +360,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -372,7 +372,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
 </div>
 <p>Note that <code>mkdir</code> is not limited to creating single
 directories one at a time. The <code>-p</code> option allows
@@ -381,7 +381,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
 </div>
 <p>The <code>-R</code> option to the <code>ls</code> command will list
 all nested subdirectories within a directory. Let’s use
@@ -390,7 +390,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -402,13 +402,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 
 ../project/results:</code></pre>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout-inner">
-<h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-ways-of-doing-the-same-thing">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a></h3>
 <div class="callout-content">
 <p>Using the shell to create a directory is no different than using a
 file explorer. If you open the current directory using your operating
@@ -419,13 +418,12 @@ <h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria
 </div>
 </div>
 </div>
-<div id="good-names-for-files-and-directories" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="good-names-for-files-and-directories" class="callout-inner">
-<h3 class="callout-title">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="good-names-for-files-and-directories">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a></h3>
 <div class="callout-content">
 <p>Complicated names of files and directories can make your life painful
 when working on the command line. Here we provide a few useful tips for
@@ -462,16 +460,15 @@ <h3 id="create-a-text-file">Create a text file<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
 </div>
-<div id="which-editor" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="which-editor" class="callout-inner">
-<h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="which-editor">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a></h3>
 <div class="callout-content">
 <p>When we say, ‘<code>nano</code> is a text editor’ we really do mean
 ‘text’. It can only work with plain character data, not tables, images,
@@ -503,13 +500,12 @@ <h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" hre
 to accept the suggested default of <code>draft.txt</code>.</p>
 <p>Once our file is saved, we can use <kbd>Ctrl</kbd>+<kbd>X</kbd> to
 quit the editor and return to the shell.</p>
-<div id="control-ctrl-or-key" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="control-ctrl-or-key" class="callout-inner">
-<h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="control-ctrl-or-key">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a></h3>
 <div class="callout-content">
 <p>The Control key is also called the ‘Ctrl’ key. There are various ways
 in which using the Control key may be described. For example, you may
@@ -534,7 +530,7 @@ <h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="a
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -554,7 +550,7 @@ <h3 class="callout-title">Creating Files a Different Way<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li><p>What did the <code>touch</code> command do? When you look at your
 current directory using the GUI file explorer, does the file show
@@ -570,7 +566,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>The <code>touch</code> command generates a new file called
 <code>my_file.txt</code> in your current directory. You can observe this
@@ -605,18 +601,17 @@ <h3 class="callout-title">Creating Files a Different Way<em>(continued)</em><a c
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
 </div>
 </div>
 </div>
 </div>
-<div id="whats-in-a-name" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="whats-in-a-name" class="callout-inner">
-<h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="whats-in-a-name">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a></h3>
 <div class="callout-content">
 <p>You may have noticed that all of Nelle’s files are named ‘something
 dot something’, and in this part of the lesson, we always used the
@@ -651,7 +646,7 @@ <h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="ancho
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
 </div>
 <p>In our <code>thesis</code> directory we have a file
 <code>draft.txt</code> which isn’t a particularly informative name, so
@@ -660,7 +655,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
 </div>
 <p>The first argument tells <code>mv</code> what we’re ‘moving’, while
 the second is where it’s to go. In this case, we’re moving
@@ -671,7 +666,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -696,7 +691,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
 </div>
 <p>The effect is to move the file from the directory it was in to the
 current working directory. <code>ls</code> now shows us that
@@ -704,7 +699,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -717,7 +712,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -732,7 +727,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -754,18 +749,18 @@ <h3 class="callout-title">Moving Files to a new folder<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
 </div>
 <p>Fill in the blanks to move these files to the <code>raw/</code>
 folder (i.e. the one she forgot to put them in)</p>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
 </div>
 </div>
 </div>
@@ -775,12 +770,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
 </div>
 <p>Recall that <code>..</code> refers to the parent directory (i.e. one
 above the current directory) and that <code>.</code> refers to the
@@ -799,8 +794,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -812,14 +807,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
 </div>
 <p>We can check the result by listing the contents of both the
 <code>thesis</code> and <code>thesis_backup</code> directory:</p>
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -837,8 +832,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
 </div>
 <div id="renaming-files" class="callout challenge">
 <div class="callout-square">
@@ -866,7 +861,7 @@ <h3 class="callout-title">Renaming Files<a class="anchor" aria-label="anchor" hr
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li>No. While this would create a file with the correct name, the
 incorrectly named file still exists in the directory and would need to
@@ -893,7 +888,7 @@ <h3 class="callout-title">Moving and Copying<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -903,7 +898,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -913,10 +908,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
-<span id="cb41-3"><a href="#cb41-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
-<span id="cb41-4"><a href="#cb41-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
+<span id="cb41-3"><a href="#cb41-3" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
+<span id="cb41-4"><a href="#cb41-4" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li><code>proteins-saved.dat recombined</code></li>
 <li><code>recombined</code></li>
@@ -930,7 +925,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We start in the <code>/Users/jamie/data</code> directory, and create
 a new folder called <code>recombined</code>. The second line moves
@@ -966,26 +961,25 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
 </div>
 <p>We can confirm the file has gone using <code>ls</code>:</p>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
 <pre class="error" tabindex="0"><code>ls: cannot access 'quotes.txt': No such file or directory</code></pre>
 </div>
-<div id="deleting-is-forever" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="deleting-is-forever" class="callout-inner">
-<h3 class="callout-title">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="deleting-is-forever">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a></h3>
 <div class="callout-content">
 <p>The Unix shell doesn’t have a trash bin that we can recover deleted
 files from (though most graphical interfaces to Unix do). Instead, when
@@ -1016,7 +1010,7 @@ <h3 class="callout-title">Using<code>rm</code>Safely<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1038,7 +1032,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1053,7 +1047,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
 </div>
 <p>Given that there is no way to retrieve files deleted using the shell,
 <code>rm -r</code> <em>should be used with great caution</em> (you might
@@ -1080,16 +1074,16 @@ <h3 class="callout-title">Copy with Multiple Filenames<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
-<span id="cb49-2"><a href="#cb49-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
+<span id="cb49-2"><a href="#cb49-2" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
 </div>
 <p>In the example below, what does <code>cp</code> do when given three
 or more file names?</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
-<span id="cb50-2"><a href="#cb50-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
+<span id="cb50-2"><a href="#cb50-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1099,7 +1093,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
 </div>
 </div>
 </div>
@@ -1109,7 +1103,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>If given more than one file name followed by a directory name
 (i.e. the destination directory must be the last argument),
@@ -1128,13 +1122,12 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 </div>
 <div class="section level3">
 <h3 id="using-wildcards-for-accessing-multiple-files-at-once">Using wildcards for accessing multiple files at once<a class="anchor" aria-label="anchor" href="#using-wildcards-for-accessing-multiple-files-at-once"></a></h3>
-<div id="wildcards" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a></h3>
 <div class="callout-content">
 <p><code>*</code> is a <strong>wildcard</strong>, which represents zero
 or more other characters. Let’s consider the
@@ -1189,7 +1182,7 @@ <h3 class="callout-title">List filenames matching a pattern<a class="anchor" ari
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The solution is <code>3.</code></p>
 <p><code>1.</code> shows all files whose names contain zero or more
@@ -1225,25 +1218,25 @@ <h3 class="callout-title">More on Wildcards<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb54">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb54-2"><a href="#cb54-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb54-3"><a href="#cb54-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb54-4"><a href="#cb54-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb54-5"><a href="#cb54-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb54-6"><a href="#cb54-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb54-7"><a href="#cb54-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb54-8"><a href="#cb54-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb54-9"><a href="#cb54-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb54-10"><a href="#cb54-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb54-11"><a href="#cb54-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb54-12"><a href="#cb54-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb54-13"><a href="#cb54-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb54-14"><a href="#cb54-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb54-15"><a href="#cb54-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb54-16"><a href="#cb54-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb54-17"><a href="#cb54-17" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb54-18"><a href="#cb54-18" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb54-19"><a href="#cb54-19" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb54-2"><a href="#cb54-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb54-3"><a href="#cb54-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb54-4"><a href="#cb54-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb54-5"><a href="#cb54-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb54-6"><a href="#cb54-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb54-7"><a href="#cb54-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb54-8"><a href="#cb54-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb54-9"><a href="#cb54-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb54-10"><a href="#cb54-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb54-11"><a href="#cb54-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb54-12"><a href="#cb54-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb54-13"><a href="#cb54-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb54-14"><a href="#cb54-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb54-15"><a href="#cb54-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb54-16"><a href="#cb54-16" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb54-17"><a href="#cb54-17" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb54-18"><a href="#cb54-18" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb54-19"><a href="#cb54-19" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
 </div>
 <p>Before heading off to another field trip, she wants to back up her
 data and send some datasets to her colleague Bob. Sam uses the following
@@ -1251,57 +1244,57 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb55">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
-<span id="cb55-2"><a href="#cb55-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
-<span id="cb55-3"><a href="#cb55-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
-<span id="cb55-4"><a href="#cb55-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
+<span id="cb55-2"><a href="#cb55-2" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
+<span id="cb55-3"><a href="#cb55-3" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
+<span id="cb55-4"><a href="#cb55-4" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 <p>Help Sam by filling in the blanks.</p>
 <p>The resulting directory structure should look like this</p>
 <div class="codewrapper sourceCode" id="cb56">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb56-2"><a href="#cb56-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb56-3"><a href="#cb56-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb56-4"><a href="#cb56-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb56-5"><a href="#cb56-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-6"><a href="#cb56-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb56-7"><a href="#cb56-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb56-8"><a href="#cb56-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb56-9"><a href="#cb56-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-10"><a href="#cb56-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-11"><a href="#cb56-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-12"><a href="#cb56-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-13"><a href="#cb56-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-14"><a href="#cb56-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb56-15"><a href="#cb56-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb56-16"><a href="#cb56-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
-<span id="cb56-17"><a href="#cb56-17" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
-<span id="cb56-18"><a href="#cb56-18" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
-<span id="cb56-19"><a href="#cb56-19" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb56-20"><a href="#cb56-20" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-21"><a href="#cb56-21" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-22"><a href="#cb56-22" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-23"><a href="#cb56-23" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
-<span id="cb56-24"><a href="#cb56-24" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
-<span id="cb56-25"><a href="#cb56-25" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-26"><a href="#cb56-26" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-27"><a href="#cb56-27" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-28"><a href="#cb56-28" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-29"><a href="#cb56-29" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb56-30"><a href="#cb56-30" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb56-31"><a href="#cb56-31" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-32"><a href="#cb56-32" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-33"><a href="#cb56-33" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-34"><a href="#cb56-34" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-35"><a href="#cb56-35" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-36"><a href="#cb56-36" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-37"><a href="#cb56-37" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
-<span id="cb56-38"><a href="#cb56-38" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-39"><a href="#cb56-39" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-40"><a href="#cb56-40" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-41"><a href="#cb56-41" aria-hidden="true" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb56-2"><a href="#cb56-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb56-3"><a href="#cb56-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb56-4"><a href="#cb56-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb56-5"><a href="#cb56-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-6"><a href="#cb56-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb56-7"><a href="#cb56-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb56-8"><a href="#cb56-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb56-9"><a href="#cb56-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-10"><a href="#cb56-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-11"><a href="#cb56-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-12"><a href="#cb56-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-13"><a href="#cb56-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-14"><a href="#cb56-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb56-15"><a href="#cb56-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb56-16"><a href="#cb56-16" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
+<span id="cb56-17"><a href="#cb56-17" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
+<span id="cb56-18"><a href="#cb56-18" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
+<span id="cb56-19"><a href="#cb56-19" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb56-20"><a href="#cb56-20" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-21"><a href="#cb56-21" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-22"><a href="#cb56-22" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-23"><a href="#cb56-23" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
+<span id="cb56-24"><a href="#cb56-24" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
+<span id="cb56-25"><a href="#cb56-25" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-26"><a href="#cb56-26" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-27"><a href="#cb56-27" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-28"><a href="#cb56-28" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-29"><a href="#cb56-29" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb56-30"><a href="#cb56-30" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb56-31"><a href="#cb56-31" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-32"><a href="#cb56-32" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-33"><a href="#cb56-33" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-34"><a href="#cb56-34" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-35"><a href="#cb56-35" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-36"><a href="#cb56-36" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-37"><a href="#cb56-37" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
+<span id="cb56-38"><a href="#cb56-38" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-39"><a href="#cb56-39" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-40"><a href="#cb56-40" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-41"><a href="#cb56-41" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -1311,14 +1304,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb57">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
-<span id="cb57-2"><a href="#cb57-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
-<span id="cb57-3"><a href="#cb57-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
+<span id="cb57-2"><a href="#cb57-2" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
+<span id="cb57-3"><a href="#cb57-3" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 </div>
 </div>
@@ -1337,7 +1330,7 @@ <h3 class="callout-title">Organizing Directories and Files<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb58">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1351,7 +1344,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb60">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1361,7 +1354,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb62">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1376,12 +1369,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
   <h4 class="accordion-header" id="headingSolution9">Show me the solution</h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb64">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" aria-hidden="true" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
 </div>
 <p>Jamie needs to move her files <code>fructose.dat</code> and
 <code>sucrose.dat</code> to the <code>analyzed</code> directory. The
@@ -1423,39 +1416,39 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb66">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb66-2"><a href="#cb66-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
-<span id="cb66-3"><a href="#cb66-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
-<span id="cb66-4"><a href="#cb66-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb66-2"><a href="#cb66-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
+<span id="cb66-3"><a href="#cb66-3" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
+<span id="cb66-4"><a href="#cb66-4" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb67">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb67-2"><a href="#cb67-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb67-3"><a href="#cb67-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb67-4"><a href="#cb67-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd data</span>
-<span id="cb67-5"><a href="#cb67-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb67-2"><a href="#cb67-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb67-3"><a href="#cb67-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb67-4"><a href="#cb67-4" tabindex="-1"></a><span class="ex">$</span> cd data</span>
+<span id="cb67-5"><a href="#cb67-5" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb68">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
-<span id="cb68-2"><a href="#cb68-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
+<span id="cb68-2"><a href="#cb68-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb69">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
-<span id="cb69-2"><a href="#cb69-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
+<span id="cb69-2"><a href="#cb69-2" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb70">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb70-2"><a href="#cb70-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb70-3"><a href="#cb70-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb70-4"><a href="#cb70-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb70-2"><a href="#cb70-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb70-3"><a href="#cb70-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb70-4"><a href="#cb70-4" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 </div>
 </div>
@@ -1465,7 +1458,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Show me the solution</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <p>The first two sets of commands achieve this objective. The first set
 uses relative paths to create the top-level directory before the
@@ -1580,7 +1573,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/03-create.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/04-pipefilter.html b/04-pipefilter.html
index d767a47fc..f75b24c46 100644
--- a/04-pipefilter.html
+++ b/04-pipefilter.html
@@ -322,7 +322,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -334,7 +334,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -351,7 +351,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -371,7 +371,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -387,20 +387,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>The <code>-m</code> and <code>-w</code> options can also be used with
 the <code>wc</code> command to show only the number of characters or the
 number of words, respectively.</p>
-<div id="why-isnt-it-doing-anything" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="why-isnt-it-doing-anything" class="callout-inner">
-<h3 class="callout-title">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="why-isnt-it-doing-anything">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a></h3>
 <div class="callout-content">
 <p>What happens if a command is supposed to process a file, but we don’t
 give it a filename? For example, what if we type:</p>
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
 </div>
 <p>but don’t type <code>*.pdb</code> (or anything else) after the
 command? Since it doesn’t have any filenames, <code>wc</code> assumes it
@@ -423,7 +422,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>The greater than symbol, <code>&gt;</code>, tells the shell to
 <strong>redirect</strong> the command’s output to a file instead of
@@ -437,7 +436,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -452,7 +451,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -465,13 +464,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   15  propane.pdb
  107  total</code></pre>
 </div>
-<div id="output-page-by-page" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="output-page-by-page" class="callout-inner">
-<h3 class="callout-title">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="output-page-by-page">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a></h3>
 <div class="callout-content">
 <p>We’ll continue to use <code>cat</code> in this lesson, for
 convenience and consistency, but it has the disadvantage that it always
@@ -533,7 +531,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>The <code>-n</code> option specifies a numerical rather than an
 alphanumerical sort.</p>
@@ -547,7 +545,7 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -570,8 +568,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
-<span id="cb20-2"><a href="#cb20-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
+<span id="cb20-2"><a href="#cb20-2" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -583,20 +581,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 20, and so on. Since <code>sorted-lengths.txt</code> contains the
 lengths of our files ordered from least to greatest, the output of
 <code>head</code> must be the file with the fewest lines.</p>
-<div id="redirecting-to-the-same-file" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="redirecting-to-the-same-file" class="callout-inner">
-<h3 class="callout-title">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="redirecting-to-the-same-file">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a></h3>
 <div class="callout-content">
 <p>It’s a very bad idea to try redirecting the output of a command that
 operates on a file to the same file. For example:</p>
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>Doing something like this may give you incorrect results and/or
 delete the contents of <code>lengths.txt</code>.</p>
@@ -619,7 +616,7 @@ <h3 class="callout-title">What Does<code>&gt;&gt;</code>Mean?<a class="anchor" a
 <div class="codewrapper sourceCode" id="cb23">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -631,13 +628,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
 </div>
 <p>and:</p>
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
 </div>
 <p>Hint: Try executing each command twice in a row and then examining
 the output files.</p>
@@ -649,7 +646,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>In the first example with <code>&gt;</code>, the string ‘hello’ is
 written to <code>testfile01.txt</code>, but the file gets overwritten
@@ -680,8 +677,8 @@ <h3 class="callout-title">Appending Data<a class="anchor" aria-label="anchor" hr
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
-<span id="cb27-2"><a href="#cb27-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
+<span id="cb27-2"><a href="#cb27-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>The first three lines of <code>animals.csv</code>
 </li>
@@ -700,7 +697,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Option 3 is correct. For option 1 to be correct we would only run the
 <code>head</code> command. For option 2 to be correct we would only run
@@ -725,7 +722,7 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -749,7 +746,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -767,7 +764,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -802,7 +799,7 @@ <h3 class="callout-title">Piping Commands Together<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Option 4 is the solution. The pipe character <code>|</code> is used
 to connect the output from one command to the input of another.
@@ -855,7 +852,7 @@ <h3 class="callout-title">Pipe Reading Comprehension<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
 </div>
 <p>Hint: build the pipeline up one command at a time to test your
 understanding</p>
@@ -867,7 +864,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>The <code>head</code> command extracts the first 5 lines from
 <code>animals.csv</code>. Then, the last 3 lines are extracted from the
@@ -897,7 +894,7 @@ <h3 class="callout-title">Pipe Construction<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
 </div>
 <p>The <code>cut</code> command is used to remove or ‘cut out’ certain
 sections of each line in the file, and <code>cut</code> expects the
@@ -931,12 +928,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -980,7 +977,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
 <div class="accordion-body">
 <p>Option 4. is the correct answer. If you have difficulty understanding
 why, try running the commands, or sub-sections of the pipelines (make
@@ -1000,8 +997,8 @@ <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <p>The output is 18 lines that look like this:</p>
 <div class="codewrapper">
@@ -1019,7 +1016,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1038,7 +1035,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1056,7 +1053,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1095,7 +1092,7 @@ <h3 class="callout-title">Removing Unneeded Files<a class="anchor" aria-label="a
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>This would remove <code>.txt</code> files with one-character
 names</p></li>
@@ -1202,7 +1199,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/04-pipefilter.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/05-loop.html b/05-loop.html
index adeec4d25..3eeee0e5d 100644
--- a/05-loop.html
+++ b/05-loop.html
@@ -327,7 +327,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
 </div>
 <p>We would like to print out the classification for each species, which
 is given on the second line of each file. For each file, we would need
@@ -338,24 +338,24 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
-<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
-<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span> </span>
-<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
-<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
-<span id="cb2-7"><a href="#cb2-7" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
-<span id="cb2-8"><a href="#cb2-8" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
+<span id="cb2-2"><a href="#cb2-2" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
+<span id="cb2-3"><a href="#cb2-3" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
+<span id="cb2-4"><a href="#cb2-4" tabindex="-1"></a><span class="cf">do</span> </span>
+<span id="cb2-5"><a href="#cb2-5" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
+<span id="cb2-6"><a href="#cb2-6" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
+<span id="cb2-7"><a href="#cb2-7" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
+<span id="cb2-8"><a href="#cb2-8" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
 </div>
 <p>and we can apply this to our example like this:</p>
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb3-3"><a href="#cb3-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb3-4"><a href="#cb3-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb3-5"><a href="#cb3-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -367,13 +367,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 unicorn.dat
 CLASSIFICATION: equus monoceros</code></pre>
 </div>
-<div id="follow-the-prompt" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="follow-the-prompt" class="callout-inner">
-<h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="follow-the-prompt">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a></h3>
 <div class="callout-content">
 <p>The shell prompt changes from <code>$</code> to <code>&gt;</code> and
 back again as we were typing in our loop. The second prompt,
@@ -413,13 +412,12 @@ <h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor"
 runs the <code>head</code> command on that file, and <code>tail</code>
 on the output of that. Since the list was only three items, the shell
 exits the <code>for</code> loop.</p>
-<div id="same-symbols-different-meanings" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="same-symbols-different-meanings" class="callout-inner">
-<h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="same-symbols-different-meanings">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a></h3>
 <div class="callout-content">
 <p>Here we see <code>&gt;</code> being used as a shell prompt, whereas
 <code>&gt;</code> is also used to redirect output. Similarly,
@@ -444,19 +442,19 @@ <h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb5-2"><a href="#cb5-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb5-3"><a href="#cb5-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb5-4"><a href="#cb5-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>or:</p>
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb6-4"><a href="#cb6-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb6-2"><a href="#cb6-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb6-3"><a href="#cb6-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb6-4"><a href="#cb6-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>it would work exactly the same way. <em>Don’t do this.</em> Programs
 are only useful if people can understand them, so meaningless names
@@ -487,15 +485,15 @@ <h3 class="callout-title">Write your own loop<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
-<span id="cb7-2"><a href="#cb7-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb7-3"><a href="#cb7-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
-<span id="cb7-4"><a href="#cb7-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
+<span id="cb7-2"><a href="#cb7-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb7-3"><a href="#cb7-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
+<span id="cb7-4"><a href="#cb7-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -535,19 +533,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
-<span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb10-2"><a href="#cb10-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb10-3"><a href="#cb10-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
+<span id="cb10-4"><a href="#cb10-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Now, what is the output of the following code?</p>
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
-<span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Why do these two loops give different outputs?</p>
 </div>
@@ -558,7 +556,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The first code block gives the same output on each iteration through
 the loop. Bash expands the wildcard <code>*.pdb</code> within the loop
@@ -568,10 +566,10 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb12-3"><a href="#cb12-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-4"><a href="#cb12-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb12-3"><a href="#cb12-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-4"><a href="#cb12-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -613,10 +611,10 @@ <h3 class="callout-title">Limiting Sets of Files<a class="anchor" aria-label="an
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
-<span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb15-3"><a href="#cb15-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb15-4"><a href="#cb15-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
+<span id="cb15-2"><a href="#cb15-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb15-3"><a href="#cb15-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb15-4"><a href="#cb15-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>No files are listed.</li>
 <li>All files are listed.</li>
@@ -631,7 +629,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so any file name starting with the letter c, followed by
@@ -652,10 +650,10 @@ <h3 class="callout-title">Limiting Sets of Files<em>(continued)</em><a class="an
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
-<span id="cb16-2"><a href="#cb16-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb16-3"><a href="#cb16-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb16-4"><a href="#cb16-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
+<span id="cb16-2"><a href="#cb16-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb16-3"><a href="#cb16-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb16-4"><a href="#cb16-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>The same files would be listed.</li>
 <li>All the files are listed this time.</li>
@@ -671,7 +669,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so a file name with zero or more characters before a letter
@@ -693,11 +691,11 @@ <h3 class="callout-title">Saving to a File in a Loop - Part One<a class="anchor"
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb17-2"><a href="#cb17-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb17-3"><a href="#cb17-3" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
-<span id="cb17-4"><a href="#cb17-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
-<span id="cb17-5"><a href="#cb17-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb17-2"><a href="#cb17-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb17-3"><a href="#cb17-3" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
+<span id="cb17-4"><a href="#cb17-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
+<span id="cb17-5"><a href="#cb17-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>Prints <code>cubane.pdb</code>, <code>ethane.pdb</code>,
 <code>methane.pdb</code>, <code>octane.pdb</code>,
@@ -720,7 +718,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li>The text from each file in turn gets written to the
 <code>alkanes.pdb</code> file. However, the file gets overwritten on
@@ -743,10 +741,10 @@ <h3 class="callout-title">Saving to a File in a Loop - Part Two<a class="anchor"
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb18-4"><a href="#cb18-4" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb18-4"><a href="#cb18-4" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>All of the text from <code>cubane.pdb</code>,
 <code>ethane.pdb</code>, <code>methane.pdb</code>,
@@ -772,7 +770,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>3 is the correct answer. <code>&gt;&gt;</code> appends to a file,
 rather than overwriting it with the redirected output from a command.
@@ -788,11 +786,11 @@ <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb19-2"><a href="#cb19-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb19-3"><a href="#cb19-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb19-4"><a href="#cb19-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb19-5"><a href="#cb19-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb19-2"><a href="#cb19-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb19-3"><a href="#cb19-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb19-4"><a href="#cb19-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb19-5"><a href="#cb19-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>The shell starts by expanding <code>*.dat</code> to create the list
 of files it will process. The <strong>loop body</strong> then executes
@@ -802,7 +800,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
 </div>
 <p>prints:</p>
 <div class="codewrapper">
@@ -816,11 +814,11 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb22-2"><a href="#cb22-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb22-3"><a href="#cb22-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
-<span id="cb22-4"><a href="#cb22-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb22-5"><a href="#cb22-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb22-2"><a href="#cb22-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb22-3"><a href="#cb22-3" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
+<span id="cb22-4"><a href="#cb22-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb22-5"><a href="#cb22-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>because then the first time through the loop, when
 <code>$filename</code> expanded to <code>basilisk.dat</code>, the shell
@@ -828,13 +826,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <code>head</code> and <code>tail</code> combination selects lines 81-100
 from whatever file is being processed (assuming the file has at least
 100 lines).</p>
-<div id="spaces-in-names" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="spaces-in-names" class="callout-inner">
-<h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="spaces-in-names">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a></h3>
 <div class="callout-content">
 <p>Spaces are used to separate the elements of the list that we are
 going to loop over. If one of those elements contains a space character,
@@ -847,10 +844,10 @@ <h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
-<span id="cb24-2"><a href="#cb24-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb24-3"><a href="#cb24-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb24-4"><a href="#cb24-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
+<span id="cb24-2"><a href="#cb24-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb24-3"><a href="#cb24-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb24-4"><a href="#cb24-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>It is simpler to avoid using spaces (or other special characters) in
 filenames.</p>
@@ -890,13 +887,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>because that would expand to:</p>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>This wouldn’t back up our files, instead we get an error:</p>
 <div class="codewrapper">
@@ -913,10 +910,10 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb30-2"><a href="#cb30-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb30-3"><a href="#cb30-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
-<span id="cb30-4"><a href="#cb30-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb30-2"><a href="#cb30-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb30-3"><a href="#cb30-3" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
+<span id="cb30-4"><a href="#cb30-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>This loop runs the <code>cp</code> command once for each filename.
 The first time, when <code>$filename</code> expands to
@@ -924,19 +921,19 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
 </div>
 <p>The second time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
 </div>
 <p>The third and last time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
 </div>
 <p>Since the <code>cp</code> command does not normally produce any
 output, it’s hard to check that the loop is working correctly. However,
@@ -963,12 +960,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -987,10 +984,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb36-3"><a href="#cb36-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb36-4"><a href="#cb36-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb36-3"><a href="#cb36-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb36-4"><a href="#cb36-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1013,14 +1010,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>Using the <kbd>←</kbd>, Nelle navigates to the <code>echo</code>
 command and changes it to <code>bash goostats.sh</code>:</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>When she presses <kbd>Enter</kbd>, the shell runs the modified
 command. However, nothing appears to happen — there is no output. After
@@ -1032,16 +1029,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
-<div id="beginning-and-end" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="beginning-and-end" class="callout-inner">
-<h3 class="callout-title">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="beginning-and-end">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a></h3>
 <div class="callout-content">
 <p>We can move to the beginning of a line in the shell by typing
 <kbd>Ctrl</kbd>+<kbd>A</kbd> and to the end using
@@ -1065,14 +1061,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <code>cat stats-NENE01729B.txt</code> to examine one of the output
 files. It looks good, so she decides to get some coffee and catch up on
 her reading.</p>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout-inner">
-<h3 class="callout-title">Those Who Know History Can Choose to Repeat
-It<a class="anchor" aria-label="anchor" href="#those-who-know-history-can-choose-to-repeat-it"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="those-who-know-history-can-choose-to-repeat-it">Those Who Know History Can Choose to Repeat
+It<a class="anchor" aria-label="anchor" href="#those-who-know-history-can-choose-to-repeat-it"></a></h3>
 <div class="callout-content">
 <p>Another way to repeat previous work is to use the
 <code>history</code> command to get a list of the last few hundred
@@ -1082,7 +1077,7 @@ <h3 class="callout-title">Those Who Know History Can Choose to Repeat
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1099,13 +1094,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 </div>
 </div>
-<div id="other-history-commands" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-history-commands" class="callout-inner">
-<h3 class="callout-title">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-history-commands">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a></h3>
 <div class="callout-content">
 <p>There are a number of other shortcut commands for getting at the
 history.</p>
@@ -1146,30 +1140,30 @@ <h3 class="callout-title">Doing a Dry Run<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb44-2"><a href="#cb44-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb44-3"><a href="#cb44-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb44-4"><a href="#cb44-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb44-2"><a href="#cb44-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb44-3"><a href="#cb44-3" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb44-4"><a href="#cb44-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>What is the difference between the two loops below, and which one
 would we want to run?</p>
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 1</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Version 1</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 2</span></span>
-<span id="cb46-2"><a href="#cb46-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb46-3"><a href="#cb46-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb46-4"><a href="#cb46-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
-<span id="cb46-5"><a href="#cb46-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="co"># Version 2</span></span>
+<span id="cb46-2"><a href="#cb46-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb46-3"><a href="#cb46-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb46-4"><a href="#cb46-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
+<span id="cb46-5"><a href="#cb46-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -1179,7 +1173,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The second version is the one we want to run. This prints to screen
 everything enclosed in the quote marks, expanding the loop variable name
@@ -1212,13 +1206,13 @@ <h3 class="callout-title">Nested Loops<a class="anchor" aria-label="anchor" href
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
-<span id="cb47-2"><a href="#cb47-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb47-3"><a href="#cb47-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
-<span id="cb47-4"><a href="#cb47-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
-<span id="cb47-5"><a href="#cb47-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
-<span id="cb47-6"><a href="#cb47-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
-<span id="cb47-7"><a href="#cb47-7" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
+<span id="cb47-2"><a href="#cb47-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb47-3"><a href="#cb47-3" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
+<span id="cb47-4"><a href="#cb47-4" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
+<span id="cb47-5"><a href="#cb47-5" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
+<span id="cb47-6"><a href="#cb47-6" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
+<span id="cb47-7"><a href="#cb47-7" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -1228,7 +1222,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <p>We have a nested loop, i.e. contained within another loop, so for
 each species in the outer loop, the inner loop (the nested loop)
@@ -1326,7 +1320,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/05-loop.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/06-script.html b/06-script.html
index 0cd5a1664..9d85d1342 100644
--- a/06-script.html
+++ b/06-script.html
@@ -326,8 +326,8 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>The command <code>nano middle.sh</code> opens the file
 <code>middle.sh</code> within the text editor ‘nano’ (which runs within
@@ -349,7 +349,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -362,13 +362,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Sure enough, our script’s output is exactly what we would get if we
 ran that pipeline directly.</p>
-<div id="text-vs.-whatever" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="text-vs.-whatever" class="callout-inner">
-<h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs.-whatever"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="text-vs--whatever">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs--whatever"></a></h3>
 <div class="callout-content">
 <p>We usually call programs like Microsoft Word or LibreOffice Writer
 “text editors”, but we need to be a bit more careful when it comes to
@@ -391,7 +390,7 @@ <h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>Now, within “nano”, replace the text <code>octane.pdb</code> with the
 special variable called <code>$1</code>:</p>
@@ -402,7 +401,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -417,7 +416,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -428,13 +427,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 ATOM     12  H           1      -0.048  -1.362  -0.205  1.00  0.00
 ATOM     13  H           1      -1.183   0.500  -1.412  1.00  0.00</code></pre>
 </div>
-<div id="double-quotes-around-arguments" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="double-quotes-around-arguments" class="callout-inner">
-<h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="double-quotes-around-arguments">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a></h3>
 <div class="callout-content">
 <p>For the same reason that we put the loop variable inside
 double-quotes, in case the filename happens to contain any spaces, we
@@ -455,14 +453,14 @@ <h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code>head -n "$2" "$1" | tail -n "$3"</code></pre>
 <p>We can now run:</p>
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -478,7 +476,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -496,7 +494,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code># Select lines from the middle of a file.
 # Usage: bash middle.sh filename end_line num_lines
@@ -513,7 +511,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <p>because <code>wc -l</code> lists the number of lines in the files
 (recall that <code>wc</code> stands for ‘word count’, adding the
@@ -533,7 +531,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
 </div>
 <pre class="source"><code># Sort files by their length.
 # Usage: bash sorted.sh one_or_more_filenames
@@ -541,7 +539,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -594,21 +592,21 @@ <h3 class="callout-title">List Unique Species<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
-<span id="cb25-2"><a href="#cb25-2" aria-hidden="true" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
-<span id="cb25-3"><a href="#cb25-3" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb25-4"><a href="#cb25-4" aria-hidden="true" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
-<span id="cb25-5"><a href="#cb25-5" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
-<span id="cb25-6"><a href="#cb25-6" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb25-7"><a href="#cb25-7" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
-<span id="cb25-8"><a href="#cb25-8" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
-<span id="cb25-9"><a href="#cb25-9" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
-<span id="cb25-10"><a href="#cb25-10" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
+<span id="cb25-2"><a href="#cb25-2" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
+<span id="cb25-3"><a href="#cb25-3" tabindex="-1"></a></span>
+<span id="cb25-4"><a href="#cb25-4" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
+<span id="cb25-5"><a href="#cb25-5" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
+<span id="cb25-6"><a href="#cb25-6" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb25-7"><a href="#cb25-7" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
+<span id="cb25-8"><a href="#cb25-8" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
+<span id="cb25-9"><a href="#cb25-9" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
+<span id="cb25-10"><a href="#cb25-10" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -622,7 +620,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
 </div>
 <p>The file <code>redo-figure-3.sh</code> now contains:</p>
 <pre class="source"><code>297 bash goostats.sh NENE01729B.txt stats-NENE01729B.txt
@@ -647,7 +645,7 @@ <h3 class="callout-title">Why Record Commands in the History Before
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
 </div>
 <p>the last command in the file is the <code>history</code> command
 itself, i.e., the shell has added <code>history</code> to the command
@@ -662,7 +660,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>If a command causes something to crash or hang, it might be useful to
 know what that command was, in order to investigate the problem. Were
@@ -687,37 +685,37 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
 </div>
 <p>She creates a file using <code>nano</code> …</p>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
 </div>
 <p>…which contains the following:</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb31-3"><a href="#cb31-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb31-4"><a href="#cb31-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb31-5"><a href="#cb31-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb31-6"><a href="#cb31-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb31-3"><a href="#cb31-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb31-4"><a href="#cb31-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb31-5"><a href="#cb31-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb31-6"><a href="#cb31-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>She saves this in a file called <code>do-stats.sh</code> so that she
 can now re-do the first stage of her analysis by typing:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>She can also do this:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
 </div>
 <p>so that the output is just the number of files processed rather than
 the names of the files that were processed.</p>
@@ -727,12 +725,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>The advantage is that this always selects the right files: she
 doesn’t have to remember to exclude the ‘Z’ files. The disadvantage is
@@ -757,15 +755,15 @@ <h3 class="callout-title">Variables in Shell Scripts<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
-<span id="cb35-2"><a href="#cb35-2" aria-hidden="true" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
+<span id="cb35-2"><a href="#cb35-2" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
 </div>
 <p>While you are in the <code>alkanes</code> directory, you type the
 following command:</p>
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
 </div>
 <p>Which of the following outputs would you expect to see?</p>
 <ol style="list-style-type: decimal"><li>All of the lines between the first and the last lines of each file
@@ -784,7 +782,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The correct answer is 2.</p>
 <p>The special variables <code>$1</code>, <code>$2</code> and
@@ -793,8 +791,8 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
-<span id="cb37-2"><a href="#cb37-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
+<span id="cb37-2"><a href="#cb37-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
 </div>
 <p>The shell does not expand <code>'*.pdb'</code> because it is enclosed
 by quote marks. As such, the first argument to the script is
@@ -820,7 +818,7 @@ <h3 class="callout-title">Find the Longest File With a Given
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
 </div>
 <p>would print the name of the <code>.pdb</code> file in
 <code>shell-lesson-data/exercise-data/alkanes</code> that has the most
@@ -829,7 +827,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -839,18 +837,18 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
-<span id="cb40-3"><a href="#cb40-3" aria-hidden="true" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
-<span id="cb40-4"><a href="#cb40-4" aria-hidden="true" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
-<span id="cb40-5"><a href="#cb40-5" aria-hidden="true" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
-<span id="cb40-6"><a href="#cb40-6" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb40-7"><a href="#cb40-7" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
+<span id="cb40-3"><a href="#cb40-3" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
+<span id="cb40-4"><a href="#cb40-4" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
+<span id="cb40-5"><a href="#cb40-5" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
+<span id="cb40-6"><a href="#cb40-6" tabindex="-1"></a></span>
+<span id="cb40-7"><a href="#cb40-7" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <p>The first part of the pipeline, <code>wc -l $1/*.$2 | sort -n</code>,
 counts the lines in each file and sorts them numerically (largest last).
@@ -883,23 +881,23 @@ <h3 class="callout-title">Script Reading Comprehension<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 1</span></span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="co"># Script 1</span></span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 2</span></span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
-<span id="cb42-3"><a href="#cb42-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb42-4"><a href="#cb42-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
-<span id="cb42-5"><a href="#cb42-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="co"># Script 2</span></span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
+<span id="cb42-3"><a href="#cb42-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb42-4"><a href="#cb42-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
+<span id="cb42-5"><a href="#cb42-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 3</span></span>
-<span id="cb43-2"><a href="#cb43-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="co"># Script 3</span></span>
+<span id="cb43-2"><a href="#cb43-2" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
 </div>
 </div>
 </div>
@@ -909,7 +907,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solutions</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>In each case, the shell expands the wildcard in <code>*.pdb</code>
 before passing the resulting list of file names as arguments to the
@@ -947,26 +945,26 @@ <h3 class="callout-title">Debugging Scripts<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb45-6"><a href="#cb45-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb45-6"><a href="#cb45-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>When you run it from the <code>north-pacific-gyre</code>
 directory:</p>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>the output is blank. To figure out why, re-run the script using the
 <code>-x</code> option:</p>
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>What is the output showing you? Which line is responsible for the
 error?</p>
@@ -978,7 +976,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>The <code>-x</code> option causes <code>bash</code> to run in debug
 mode. This prints out each command as it is run, which will help you to
@@ -1074,7 +1072,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/06-script.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/07-find.html b/07-find.html
index e8bd4b6ac..fdd94c40c 100644
--- a/07-find.html
+++ b/07-find.html
@@ -319,9 +319,9 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
-<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
+<span id="cb1-3"><a href="#cb1-3" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -342,7 +342,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -365,7 +365,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -384,7 +384,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -398,7 +398,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -415,7 +415,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -433,7 +433,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -446,7 +446,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -461,7 +461,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -484,7 +484,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -499,7 +499,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -550,7 +550,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The correct answer is 3, because the <code>-w</code> option looks
 only for whole-word matches. The other options will also match ‘of’ when
@@ -559,13 +559,12 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="wildcards" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a></h3>
 <div class="callout-content">
 <p><code>grep</code>‘s real power doesn’t come from its options, though;
 it comes from the fact that patterns can include wildcards. (The
@@ -578,7 +577,7 @@ <h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -629,13 +628,13 @@ <h3 class="callout-title">Tracking a Species<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span></span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-6"><a href="#cb28-6" aria-hidden="true" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
-<span id="cb28-7"><a href="#cb28-7" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a><span class="op">&gt;</span></span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-6"><a href="#cb28-6" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
+<span id="cb28-7"><a href="#cb28-7" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
 </div>
 <p>Hint: use <code>man grep</code> to look for how to grep text
 recursively in a directory and <code>man cut</code> to select more than
@@ -650,7 +649,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <pre class="source"><code>grep -w $1 -r $2 | cut -d : -f 2 | cut -d , -f 1,3 &gt; $1.txt</code></pre>
 <p>Actually, you can swap the order of the two cut commands and it still
@@ -661,7 +660,7 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
 </div>
 </div>
 </div>
@@ -698,7 +697,7 @@ <h3 class="callout-title">Little Women<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solutions</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <pre class="source"><code>for sis in Jo Meg Beth Amy
 do
@@ -761,7 +760,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -797,7 +796,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -814,7 +813,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -837,7 +836,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -852,7 +851,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
 </div>
 <p><code>find</code> did what we asked; we just asked for the wrong
 thing.</p>
@@ -864,7 +863,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -873,13 +872,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <span><span class="va">.</span><span class="op">/</span><span class="va">writing</span><span class="op">/</span><span class="va">haiku.txt</span></span>
 <span><span class="va">.</span><span class="op">/</span><span class="va">numbers.txt</span></span></code></pre>
 </div>
-<div id="listing-vs.-finding" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="listing-vs.-finding" class="callout-inner">
-<h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs.-finding"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="listing-vs--finding">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs--finding"></a></h3>
 <div class="callout-content">
 <p><code>ls</code> and <code>find</code> can be made to do similar
 things given the right options, but under normal circumstances,
@@ -898,7 +896,7 @@ <h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -918,7 +916,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
 </div>
 <p>which is what we wanted. This expansion is exactly what the shell
 does when it expands wildcards like <code>*</code> and <code>?</code>,
@@ -932,7 +930,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -966,7 +964,7 @@ <h3 class="callout-title">Matching and Subtracting<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>Option 1 is correct. Putting the match expression in quotes prevents
 the shell expanding it, so it gets passed to the <code>find</code>
@@ -982,13 +980,12 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="binary-files" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="binary-files" class="callout-inner">
-<h3 class="callout-title">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="binary-files">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a></h3>
 <div class="callout-content">
 <p>We have focused exclusively on finding patterns in text files. What
 if your data is stored as images, in databases, or in some other
@@ -1033,7 +1030,7 @@ <h3 class="callout-title">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -1043,7 +1040,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>Find all files with a <code>.dat</code> extension recursively
 from the current directory</p></li>
@@ -1140,7 +1137,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/07-find.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/404.html b/404.html
index 964b47783..f82652a50 100644
--- a/404.html
+++ b/404.html
@@ -319,8 +319,8 @@ <h1>Page not found</h1>
   "url": "https://swcarpentry.github.io/shell-novice/404.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/404.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/CODE_OF_CONDUCT.html b/CODE_OF_CONDUCT.html
index 21d088115..14b0ce45f 100644
--- a/CODE_OF_CONDUCT.html
+++ b/CODE_OF_CONDUCT.html
@@ -337,7 +337,7 @@ <h1>Contributor Code of Conduct</h1>
   "identifier": "https://swcarpentry.github.io/shell-novice/CODE_OF_CONDUCT.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/LICENSE.html b/LICENSE.html
index 7fa3d32eb..6a3f18f32 100644
--- a/LICENSE.html
+++ b/LICENSE.html
@@ -389,7 +389,7 @@ <h1>Licenses</h1>
   "identifier": "https://swcarpentry.github.io/shell-novice/LICENSE.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/aio.html b/aio.html
index 82459a55b..19c263730 100644
--- a/aio.html
+++ b/aio.html
@@ -405,7 +405,7 @@ <h3 id="the-shell">The Shell<a class="anchor" aria-label="anchor" href="#the-she
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
 </div>
 <p>The shell typically uses <code>$</code> as the prompt, but may use a
 different symbol. In the examples for this lesson, we’ll show the prompt
@@ -425,7 +425,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
 </div>
 <p>The prompt might even include more than this. Do not worry if your
 prompt is not just a short <code>$</code>. This lesson does not depend
@@ -438,7 +438,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -446,12 +446,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="output" tabindex="0"><code>Desktop     Downloads   Movies      Pictures
 Documents   Library     Music       Public</code></pre>
 </div>
-<div id="command-not-found" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="command-not-found" class="callout-inner">
-<h3 class="callout-title">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="command-not-found">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a>
 </h3>
 <div class="callout-content">
 <p>If the shell can’t find a program whose name is the command you
@@ -459,7 +459,7 @@ <h3 class="callout-title">Command not found<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -593,7 +593,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -602,12 +602,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Here, the computer’s response is <code>/Users/nelle</code>, which is
 Nelle’s <strong>home directory</strong>:</p>
-<div id="home-directory-variation" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="home-directory-variation" class="callout-inner">
-<h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="home-directory-variation">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a>
 </h3>
 <div class="callout-content">
 <p>The home directory path will look different on different operating
@@ -647,12 +647,12 @@ <h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="
 first part of its name. Similarly, we know that <code>/Users</code> is
 stored inside the root directory <code>/</code> because its name begins
 with <code>/</code>.</p>
-<div id="slashes" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="slashes" class="callout-inner">
-<h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="slashes">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a>
 </h3>
 <div class="callout-content">
 <p>Notice that there are two meanings for the <code>/</code> character.
@@ -678,7 +678,7 @@ <h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#sl
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -705,7 +705,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -717,12 +717,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <strong>sub-directories</strong>. Any names in the output that don’t
 have a classification symbol are <strong>files</strong> in the current
 working directory.</p>
-<div id="clearing-your-terminal" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="clearing-your-terminal" class="callout-inner">
-<h3 class="callout-title">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="clearing-your-terminal">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a>
 </h3>
 <div class="callout-content">
 <p>If your screen gets too cluttered, you can clear your terminal using
@@ -746,7 +746,7 @@ <h3 id="getting-help">Getting help<a class="anchor" aria-label="anchor" href="#g
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <ol start="2" style="list-style-type: decimal">
 <li>We can read its manual with <code>man</code> (available on Linux and
@@ -755,15 +755,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>We’ll describe both ways next.</p>
-<div id="help-for-built-in-commands" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="help-for-built-in-commands" class="callout-inner">
-<h3 class="callout-title">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="help-for-built-in-commands">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a>
 </h3>
 <div class="callout-content">
 <p>Some commands are built in to the Bash shell, rather than existing as
@@ -784,7 +784,7 @@ <h4 id="the---help-option">The <code>--help</code> option<a class="anchor" aria-
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -815,12 +815,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   -F, --classify             append indicator (one of */=&gt;@|) to entries
 ...        ...        ...</code></pre>
 </div>
-<div id="unsupported-command-line-options" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="unsupported-command-line-options" class="callout-inner">
-<h3 class="callout-title">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="unsupported-command-line-options">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a>
 </h3>
 <div class="callout-content">
 <p>If you try to use an option that is not supported, <code>ls</code>
@@ -828,7 +828,7 @@ <h3 class="callout-title">Unsupported command-line options<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -847,7 +847,7 @@ <h4 id="the-man-command">The <code>man</code> command<a class="anchor" aria-labe
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>This command will turn your terminal into a page with a description
 of the <code>ls</code> command and its options.</p>
@@ -861,12 +861,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <kbd>Shift</kbd>+<kbd>N</kbd> (for moving backward).</p>
 <p>To <strong>quit</strong> the <code>man</code> pages, press
 <kbd>Q</kbd>.</p>
-<div id="manual-pages-on-the-web" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="manual-pages-on-the-web" class="callout-inner">
-<h3 class="callout-title">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="manual-pages-on-the-web">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a>
 </h3>
 <div class="callout-content">
 <p>Of course, there is a third way to access help for commands:
@@ -902,7 +902,7 @@ <h3 class="callout-title">Exploring More<code>ls</code>Options<a class="anchor"
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>-l</code> option makes <code>ls</code> use a
 <strong>l</strong>ong listing format, showing not only the
@@ -938,7 +938,7 @@ <h3 class="callout-title">Listing in Reverse Chronological Order<a class="anchor
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The most recently changed file is listed last when using
 <code>-rt</code>. This can be very useful for finding your most recent
@@ -963,7 +963,7 @@ <h3 id="exploring-other-directories">Exploring Other Directories<a class="anchor
 <div class="codewrapper sourceCode" id="cb14">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -994,7 +994,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1016,9 +1016,9 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
 </div>
 <p>These commands will move us from our home directory into our Desktop
 directory, then into the <code>shell-lesson-data</code> directory, then
@@ -1035,7 +1035,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1045,7 +1045,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1058,7 +1058,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb23">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1075,7 +1075,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
 </div>
 <p><code>..</code> is a special directory name meaning “the directory
 containing this one”, or more succinctly, the <strong>parent</strong> of
@@ -1085,7 +1085,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1098,7 +1098,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1116,12 +1116,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>Note that in most command line tools, multiple options can be
 combined with a single <code>-</code> and no spaces between the options;
 <code>ls -F -a</code> is equivalent to <code>ls -Fa</code>.</p>
-<div id="other-hidden-files" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-hidden-files" class="callout-inner">
-<h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-hidden-files">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a>
 </h3>
 <div class="callout-content">
 <p>In addition to the hidden directories <code>..</code> and
@@ -1144,14 +1144,14 @@ <h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
 </div>
 <p>How can you check what happened? <code>pwd</code> gives us the
 answer!</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1168,7 +1168,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
 </div>
 <p>Check that we’ve moved to the right place by running <code>pwd</code>
 and <code>ls -F</code>.</p>
@@ -1194,7 +1194,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1204,16 +1204,16 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Run <code>pwd</code> and <code>ls -F</code> to ensure that we’re in
 the directory we expect.</p>
-<div id="two-more-shortcuts" class="callout callout">
+<div id="callout8" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-more-shortcuts" class="callout-inner">
-<h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-more-shortcuts">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a>
 </h3>
 <div class="callout-content">
 <p>The shell interprets a tilde (<code>~</code>) character at the start
@@ -1238,20 +1238,20 @@ <h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Then <code>cd</code> into the <code>exercise-data/creatures</code>
 directory</p>
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
 </div>
 <p>Now if you run</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
 </div>
 <p>you’ll see you’re back in <code>~/Desktop/shell-lesson-data</code>.
 Run <code>cd -</code> again and you’re back in
@@ -1289,7 +1289,7 @@ <h3 class="callout-title">Absolute vs Relative Paths<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>No: <code>.</code> stands for the current directory.</p></li>
@@ -1335,7 +1335,7 @@ <h3 class="callout-title">Relative Path Resolution<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>No: there <em>is</em> a directory <code>backup</code> in
@@ -1381,7 +1381,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>No: <code>pwd</code> is not the name of a directory.</p></li>
@@ -1404,7 +1404,7 @@ <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <figure><img src="fig/shell_command_syntax.svg" alt="General syntax of a shell command" class="figure mx-auto d-block"></figure><p><code>ls</code> is the <strong>command</strong>, with an
 <strong>option</strong> <code>-F</code> and an <strong>argument</strong>
@@ -1430,8 +1430,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1446,7 +1446,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1460,7 +1460,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1469,12 +1469,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 Library/              Users/
 Network/              Volumes/</code></pre>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout callout">
+<div id="callout9" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout-inner">
-<h3 class="callout-title">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="when-to-use-short-or-long-options">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a>
 </h3>
 <div class="callout-content">
 <p>When options exist as both short and long options:</p>
@@ -1508,7 +1508,7 @@ <h3 id="nelles-pipeline-organizing-files">Nelle’s Pipeline: Organizing Files<a
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>This command is a lot to type, but she can let the shell do most of
 the work through what is called <strong>tab completion</strong>. If she
@@ -1516,14 +1516,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
 </div>
 <p>and then presses <kbd>Tab</kbd> (the tab key on her keyboard), the
 shell automatically completes the directory name for her:</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>Pressing <kbd>Tab</kbd> again does nothing, since there are multiple
 possibilities; pressing <kbd>Tab</kbd> twice brings up a list of all the
@@ -1534,15 +1534,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb51">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
 </div>
 <p>To see all of those files, she can press <kbd>Tab</kbd> twice
 more.</p>
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
-<span id="cb52-2"><a href="#cb52-2" aria-hidden="true" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
+<span id="cb52-2"><a href="#cb52-2" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
 </div>
 <p>This is called <strong>tab completion</strong>, and we will see it in
 many other tools as we go on.</p>
@@ -1641,7 +1641,7 @@ <h3 id="step-one-see-where-we-are-and-what-we-already-have">Step one: see where
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
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 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1670,7 +1670,7 @@ <h3 id="create-a-directory">Create a directory<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
 </div>
 <p>As you might guess from its name, <code>mkdir</code> means ‘make
 directory’. Since <code>thesis</code> is a relative path (i.e., does not
@@ -1679,7 +1679,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1691,7 +1691,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
 </div>
 <p>Note that <code>mkdir</code> is not limited to creating single
 directories one at a time. The <code>-p</code> option allows
@@ -1700,7 +1700,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
 </div>
 <p>The <code>-R</code> option to the <code>ls</code> command will list
 all nested subdirectories within a directory. Let’s use
@@ -1709,7 +1709,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1721,12 +1721,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 
 ../project/results:</code></pre>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout-inner">
-<h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-ways-of-doing-the-same-thing">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a>
 </h3>
 <div class="callout-content">
 <p>Using the shell to create a directory is no different than using a
@@ -1738,12 +1738,12 @@ <h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria
 </div>
 </div>
 </div>
-<div id="good-names-for-files-and-directories" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="good-names-for-files-and-directories" class="callout-inner">
-<h3 class="callout-title">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="good-names-for-files-and-directories">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a>
 </h3>
 <div class="callout-content">
 <p>Complicated names of files and directories can make your life painful
@@ -1788,15 +1788,15 @@ <h3 id="create-a-text-file">Create a text file<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb12">
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
 </div>
-<div id="which-editor" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="which-editor" class="callout-inner">
-<h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="which-editor">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a>
 </h3>
 <div class="callout-content">
 <p>When we say, ‘<code>nano</code> is a text editor’ we really do mean
@@ -1829,12 +1829,12 @@ <h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" hre
 to accept the suggested default of <code>draft.txt</code>.</p>
 <p>Once our file is saved, we can use <kbd>Ctrl</kbd>+<kbd>X</kbd> to
 quit the editor and return to the shell.</p>
-<div id="control-ctrl-or-key" class="callout callout">
+<div id="callout4" class="callout">
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 </div>
-<div id="control-ctrl-or-key" class="callout-inner">
-<h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="control-ctrl-or-key">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a>
 </h3>
 <div class="callout-content">
 <p>The Control key is also called the ‘Ctrl’ key. There are various ways
@@ -1862,7 +1862,7 @@ <h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="a
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1882,7 +1882,7 @@ <h3 class="callout-title">Creating Files a Different Way<a class="anchor" aria-l
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li><p>What did the <code>touch</code> command do? When you look at your
@@ -1900,7 +1900,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>The <code>touch</code> command generates a new file called
@@ -1937,17 +1937,17 @@ <h3 class="callout-title">Creating Files a Different Way<em>(continued)</em><a c
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
 </div>
 </div>
 </div>
 </div>
-<div id="whats-in-a-name" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="whats-in-a-name" class="callout-inner">
-<h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="whats-in-a-name">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a>
 </h3>
 <div class="callout-content">
 <p>You may have noticed that all of Nelle’s files are named ‘something
@@ -1984,7 +1984,7 @@ <h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="ancho
 <div class="codewrapper sourceCode" id="cb17">
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
 </div>
 <p>In our <code>thesis</code> directory we have a file
 <code>draft.txt</code> which isn’t a particularly informative name, so
@@ -1993,7 +1993,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
 </div>
 <p>The first argument tells <code>mv</code> what we’re ‘moving’, while
 the second is where it’s to go. In this case, we’re moving
@@ -2004,7 +2004,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
 </div>
 <p>The effect is to move the file from the directory it was in to the
 current working directory. <code>ls</code> now shows us that
@@ -2037,7 +2037,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2050,7 +2050,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2065,7 +2065,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb26">
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2087,18 +2087,18 @@ <h3 class="callout-title">Moving Files to a new folder<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
 </div>
 <p>Fill in the blanks to move these files to the <code>raw/</code>
 folder (i.e. the one she forgot to put them in)</p>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
 </div>
 </div>
 </div>
@@ -2108,12 +2108,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
 </div>
 <p>Recall that <code>..</code> refers to the parent directory (i.e. one
 above the current directory) and that <code>.</code> refers to the
@@ -2133,8 +2133,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2146,14 +2146,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
 </div>
 <p>We can check the result by listing the contents of both the
 <code>thesis</code> and <code>thesis_backup</code> directory:</p>
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2171,8 +2171,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
 </div>
 <div id="renaming-files" class="callout challenge">
 <div class="callout-square">
@@ -2202,7 +2202,7 @@ <h3 class="callout-title">Renaming Files<a class="anchor" aria-label="anchor" hr
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li>No. While this would create a file with the correct name, the
@@ -2231,7 +2231,7 @@ <h3 class="callout-title">Moving and Copying<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2241,7 +2241,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2251,10 +2251,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
-<span id="cb41-3"><a href="#cb41-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
-<span id="cb41-4"><a href="#cb41-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
+<span id="cb41-3"><a href="#cb41-3" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
+<span id="cb41-4"><a href="#cb41-4" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li><code>proteins-saved.dat recombined</code></li>
@@ -2270,7 +2270,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We start in the <code>/Users/jamie/data</code> directory, and create
 a new folder called <code>recombined</code>. The second line moves
@@ -2309,25 +2309,25 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
 </div>
 <p>We can confirm the file has gone using <code>ls</code>:</p>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
 <pre class="error" tabindex="0"><code>ls: cannot access 'quotes.txt': No such file or directory</code></pre>
 </div>
-<div id="deleting-is-forever" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="deleting-is-forever" class="callout-inner">
-<h3 class="callout-title">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="deleting-is-forever">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a>
 </h3>
 <div class="callout-content">
 <p>The Unix shell doesn’t have a trash bin that we can recover deleted
@@ -2359,7 +2359,7 @@ <h3 class="callout-title">Using<code>rm</code>Safely<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2381,7 +2381,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2396,7 +2396,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
 </div>
 <p>Given that there is no way to retrieve files deleted using the shell,
 <code>rm -r</code> <em>should be used with great caution</em> (you might
@@ -2424,16 +2424,16 @@ <h3 class="callout-title">Copy with Multiple Filenames<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
-<span id="cb49-2"><a href="#cb49-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
+<span id="cb49-2"><a href="#cb49-2" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
 </div>
 <p>In the example below, what does <code>cp</code> do when given three
 or more file names?</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
-<span id="cb50-2"><a href="#cb50-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
+<span id="cb50-2"><a href="#cb50-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2443,7 +2443,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
 </div>
 </div>
 </div>
@@ -2453,7 +2453,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>If given more than one file name followed by a directory name
 (i.e. the destination directory must be the last argument),
@@ -2473,12 +2473,12 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="section level3">
 <h3 id="using-wildcards-for-accessing-multiple-files-at-once">Using wildcards for accessing multiple files at once<a class="anchor" aria-label="anchor" href="#using-wildcards-for-accessing-multiple-files-at-once"></a>
 </h3>
-<div id="wildcards" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
 </h3>
 <div class="callout-content">
 <p><code>*</code> is a <strong>wildcard</strong>, which represents zero
@@ -2536,7 +2536,7 @@ <h3 class="callout-title">List filenames matching a pattern<a class="anchor" ari
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The solution is <code>3.</code></p>
 <p><code>1.</code> shows all files whose names contain zero or more
@@ -2572,25 +2572,25 @@ <h3 class="callout-title">More on Wildcards<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb54">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb54-2"><a href="#cb54-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb54-3"><a href="#cb54-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb54-4"><a href="#cb54-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb54-5"><a href="#cb54-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb54-6"><a href="#cb54-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb54-7"><a href="#cb54-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb54-8"><a href="#cb54-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb54-9"><a href="#cb54-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb54-10"><a href="#cb54-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb54-11"><a href="#cb54-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb54-12"><a href="#cb54-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb54-13"><a href="#cb54-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb54-14"><a href="#cb54-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb54-15"><a href="#cb54-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb54-16"><a href="#cb54-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb54-17"><a href="#cb54-17" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb54-18"><a href="#cb54-18" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb54-19"><a href="#cb54-19" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb54-2"><a href="#cb54-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb54-3"><a href="#cb54-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb54-4"><a href="#cb54-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb54-5"><a href="#cb54-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb54-6"><a href="#cb54-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb54-7"><a href="#cb54-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb54-8"><a href="#cb54-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb54-9"><a href="#cb54-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb54-10"><a href="#cb54-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb54-11"><a href="#cb54-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb54-12"><a href="#cb54-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb54-13"><a href="#cb54-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb54-14"><a href="#cb54-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb54-15"><a href="#cb54-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb54-16"><a href="#cb54-16" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb54-17"><a href="#cb54-17" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb54-18"><a href="#cb54-18" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb54-19"><a href="#cb54-19" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
 </div>
 <p>Before heading off to another field trip, she wants to back up her
 data and send some datasets to her colleague Bob. Sam uses the following
@@ -2598,57 +2598,57 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb55">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
-<span id="cb55-2"><a href="#cb55-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
-<span id="cb55-3"><a href="#cb55-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
-<span id="cb55-4"><a href="#cb55-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
+<span id="cb55-2"><a href="#cb55-2" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
+<span id="cb55-3"><a href="#cb55-3" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
+<span id="cb55-4"><a href="#cb55-4" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 <p>Help Sam by filling in the blanks.</p>
 <p>The resulting directory structure should look like this</p>
 <div class="codewrapper sourceCode" id="cb56">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb56-2"><a href="#cb56-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb56-3"><a href="#cb56-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb56-4"><a href="#cb56-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb56-5"><a href="#cb56-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-6"><a href="#cb56-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb56-7"><a href="#cb56-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb56-8"><a href="#cb56-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb56-9"><a href="#cb56-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-10"><a href="#cb56-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-11"><a href="#cb56-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-12"><a href="#cb56-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-13"><a href="#cb56-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-14"><a href="#cb56-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb56-15"><a href="#cb56-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb56-16"><a href="#cb56-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
-<span id="cb56-17"><a href="#cb56-17" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
-<span id="cb56-18"><a href="#cb56-18" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
-<span id="cb56-19"><a href="#cb56-19" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb56-20"><a href="#cb56-20" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-21"><a href="#cb56-21" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-22"><a href="#cb56-22" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-23"><a href="#cb56-23" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
-<span id="cb56-24"><a href="#cb56-24" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
-<span id="cb56-25"><a href="#cb56-25" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-26"><a href="#cb56-26" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-27"><a href="#cb56-27" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-28"><a href="#cb56-28" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-29"><a href="#cb56-29" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb56-30"><a href="#cb56-30" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb56-31"><a href="#cb56-31" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-32"><a href="#cb56-32" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-33"><a href="#cb56-33" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-34"><a href="#cb56-34" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-35"><a href="#cb56-35" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-36"><a href="#cb56-36" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-37"><a href="#cb56-37" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
-<span id="cb56-38"><a href="#cb56-38" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-39"><a href="#cb56-39" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-40"><a href="#cb56-40" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-41"><a href="#cb56-41" aria-hidden="true" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb56-2"><a href="#cb56-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb56-3"><a href="#cb56-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb56-4"><a href="#cb56-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb56-5"><a href="#cb56-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-6"><a href="#cb56-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb56-7"><a href="#cb56-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb56-8"><a href="#cb56-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb56-9"><a href="#cb56-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-10"><a href="#cb56-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-11"><a href="#cb56-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-12"><a href="#cb56-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-13"><a href="#cb56-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-14"><a href="#cb56-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb56-15"><a href="#cb56-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb56-16"><a href="#cb56-16" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
+<span id="cb56-17"><a href="#cb56-17" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
+<span id="cb56-18"><a href="#cb56-18" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
+<span id="cb56-19"><a href="#cb56-19" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb56-20"><a href="#cb56-20" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-21"><a href="#cb56-21" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-22"><a href="#cb56-22" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-23"><a href="#cb56-23" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
+<span id="cb56-24"><a href="#cb56-24" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
+<span id="cb56-25"><a href="#cb56-25" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-26"><a href="#cb56-26" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-27"><a href="#cb56-27" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-28"><a href="#cb56-28" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-29"><a href="#cb56-29" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb56-30"><a href="#cb56-30" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb56-31"><a href="#cb56-31" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-32"><a href="#cb56-32" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-33"><a href="#cb56-33" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-34"><a href="#cb56-34" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-35"><a href="#cb56-35" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-36"><a href="#cb56-36" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-37"><a href="#cb56-37" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
+<span id="cb56-38"><a href="#cb56-38" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-39"><a href="#cb56-39" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-40"><a href="#cb56-40" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-41"><a href="#cb56-41" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -2658,14 +2658,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb57">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
-<span id="cb57-2"><a href="#cb57-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
-<span id="cb57-3"><a href="#cb57-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
+<span id="cb57-2"><a href="#cb57-2" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
+<span id="cb57-3"><a href="#cb57-3" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 </div>
 </div>
@@ -2684,7 +2684,7 @@ <h3 class="callout-title">Organizing Directories and Files<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb58">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2698,7 +2698,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb60">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2708,7 +2708,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb62">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2723,12 +2723,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
   <h4 class="accordion-header" id="headingSolution9">Show me the solution</h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb64">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" aria-hidden="true" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
 </div>
 <p>Jamie needs to move her files <code>fructose.dat</code> and
 <code>sucrose.dat</code> to the <code>analyzed</code> directory. The
@@ -2770,39 +2770,39 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb66">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb66-2"><a href="#cb66-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
-<span id="cb66-3"><a href="#cb66-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
-<span id="cb66-4"><a href="#cb66-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb66-2"><a href="#cb66-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
+<span id="cb66-3"><a href="#cb66-3" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
+<span id="cb66-4"><a href="#cb66-4" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb67">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb67-2"><a href="#cb67-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb67-3"><a href="#cb67-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb67-4"><a href="#cb67-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd data</span>
-<span id="cb67-5"><a href="#cb67-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb67-2"><a href="#cb67-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb67-3"><a href="#cb67-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb67-4"><a href="#cb67-4" tabindex="-1"></a><span class="ex">$</span> cd data</span>
+<span id="cb67-5"><a href="#cb67-5" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb68">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
-<span id="cb68-2"><a href="#cb68-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
+<span id="cb68-2"><a href="#cb68-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb69">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
-<span id="cb69-2"><a href="#cb69-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
+<span id="cb69-2"><a href="#cb69-2" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb70">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb70-2"><a href="#cb70-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb70-3"><a href="#cb70-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb70-4"><a href="#cb70-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb70-2"><a href="#cb70-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb70-3"><a href="#cb70-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb70-4"><a href="#cb70-4" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 </div>
 </div>
@@ -2812,7 +2812,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Show me the solution</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <p>The first two sets of commands achieve this objective. The first set
 uses relative paths to create the top-level directory before the
@@ -2919,7 +2919,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2931,7 +2931,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2948,7 +2948,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2968,7 +2968,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2984,12 +2984,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>The <code>-m</code> and <code>-w</code> options can also be used with
 the <code>wc</code> command to show only the number of characters or the
 number of words, respectively.</p>
-<div id="why-isnt-it-doing-anything" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="why-isnt-it-doing-anything" class="callout-inner">
-<h3 class="callout-title">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="why-isnt-it-doing-anything">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a>
 </h3>
 <div class="callout-content">
 <p>What happens if a command is supposed to process a file, but we don’t
@@ -2997,7 +2997,7 @@ <h3 class="callout-title">Why Isn’t It Doing Anything?<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
 </div>
 <p>but don’t type <code>*.pdb</code> (or anything else) after the
 command? Since it doesn’t have any filenames, <code>wc</code> assumes it
@@ -3021,7 +3021,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>The greater than symbol, <code>&gt;</code>, tells the shell to
 <strong>redirect</strong> the command’s output to a file instead of
@@ -3035,7 +3035,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3050,7 +3050,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3063,12 +3063,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   15  propane.pdb
  107  total</code></pre>
 </div>
-<div id="output-page-by-page" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="output-page-by-page" class="callout-inner">
-<h3 class="callout-title">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="output-page-by-page">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a>
 </h3>
 <div class="callout-content">
 <p>We’ll continue to use <code>cat</code> in this lesson, for
@@ -3132,7 +3132,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>The <code>-n</code> option specifies a numerical rather than an
 alphanumerical sort.</p>
@@ -3146,7 +3146,7 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3169,8 +3169,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
-<span id="cb20-2"><a href="#cb20-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
+<span id="cb20-2"><a href="#cb20-2" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3182,12 +3182,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 20, and so on. Since <code>sorted-lengths.txt</code> contains the
 lengths of our files ordered from least to greatest, the output of
 <code>head</code> must be the file with the fewest lines.</p>
-<div id="redirecting-to-the-same-file" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="redirecting-to-the-same-file" class="callout-inner">
-<h3 class="callout-title">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="redirecting-to-the-same-file">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a>
 </h3>
 <div class="callout-content">
 <p>It’s a very bad idea to try redirecting the output of a command that
@@ -3195,7 +3195,7 @@ <h3 class="callout-title">Redirecting to the same file<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>Doing something like this may give you incorrect results and/or
 delete the contents of <code>lengths.txt</code>.</p>
@@ -3218,7 +3218,7 @@ <h3 class="callout-title">What Does<code>&gt;&gt;</code>Mean?<a class="anchor" a
 <div class="codewrapper sourceCode" id="cb23">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3230,13 +3230,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
 </div>
 <p>and:</p>
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
 </div>
 <p>Hint: Try executing each command twice in a row and then examining
 the output files.</p>
@@ -3248,7 +3248,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>In the first example with <code>&gt;</code>, the string ‘hello’ is
 written to <code>testfile01.txt</code>, but the file gets overwritten
@@ -3279,8 +3279,8 @@ <h3 class="callout-title">Appending Data<a class="anchor" aria-label="anchor" hr
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
-<span id="cb27-2"><a href="#cb27-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
+<span id="cb27-2"><a href="#cb27-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>The first three lines of <code>animals.csv</code>
@@ -3301,7 +3301,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Option 3 is correct. For option 1 to be correct we would only run the
 <code>head</code> command. For option 2 to be correct we would only run
@@ -3327,7 +3327,7 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3352,7 +3352,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3370,7 +3370,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3407,7 +3407,7 @@ <h3 class="callout-title">Piping Commands Together<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Option 4 is the solution. The pipe character <code>|</code> is used
 to connect the output from one command to the input of another.
@@ -3461,7 +3461,7 @@ <h3 class="callout-title">Pipe Reading Comprehension<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
 </div>
 <p>Hint: build the pipeline up one command at a time to test your
 understanding</p>
@@ -3473,7 +3473,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>The <code>head</code> command extracts the first 5 lines from
 <code>animals.csv</code>. Then, the last 3 lines are extracted from the
@@ -3503,7 +3503,7 @@ <h3 class="callout-title">Pipe Construction<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
 </div>
 <p>The <code>cut</code> command is used to remove or ‘cut out’ certain
 sections of each line in the file, and <code>cut</code> expects the
@@ -3537,12 +3537,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -3588,7 +3588,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
 <div class="accordion-body">
 <p>Option 4. is the correct answer. If you have difficulty understanding
 why, try running the commands, or sub-sections of the pipelines (make
@@ -3609,8 +3609,8 @@ <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <p>The output is 18 lines that look like this:</p>
 <div class="codewrapper">
@@ -3628,7 +3628,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3647,7 +3647,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3665,7 +3665,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3706,7 +3706,7 @@ <h3 class="callout-title">Removing Unneeded Files<a class="anchor" aria-label="a
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>This would remove <code>.txt</code> files with one-character
@@ -3817,7 +3817,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
 </div>
 <p>We would like to print out the classification for each species, which
 is given on the second line of each file. For each file, we would need
@@ -3828,24 +3828,24 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
-<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
-<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span> </span>
-<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
-<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
-<span id="cb2-7"><a href="#cb2-7" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
-<span id="cb2-8"><a href="#cb2-8" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
+<span id="cb2-2"><a href="#cb2-2" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
+<span id="cb2-3"><a href="#cb2-3" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
+<span id="cb2-4"><a href="#cb2-4" tabindex="-1"></a><span class="cf">do</span> </span>
+<span id="cb2-5"><a href="#cb2-5" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
+<span id="cb2-6"><a href="#cb2-6" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
+<span id="cb2-7"><a href="#cb2-7" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
+<span id="cb2-8"><a href="#cb2-8" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
 </div>
 <p>and we can apply this to our example like this:</p>
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb3-3"><a href="#cb3-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb3-4"><a href="#cb3-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb3-5"><a href="#cb3-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3857,12 +3857,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 unicorn.dat
 CLASSIFICATION: equus monoceros</code></pre>
 </div>
-<div id="follow-the-prompt" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="follow-the-prompt" class="callout-inner">
-<h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="follow-the-prompt">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a>
 </h3>
 <div class="callout-content">
 <p>The shell prompt changes from <code>$</code> to <code>&gt;</code> and
@@ -3903,12 +3903,12 @@ <h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor"
 runs the <code>head</code> command on that file, and <code>tail</code>
 on the output of that. Since the list was only three items, the shell
 exits the <code>for</code> loop.</p>
-<div id="same-symbols-different-meanings" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="same-symbols-different-meanings" class="callout-inner">
-<h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="same-symbols-different-meanings">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a>
 </h3>
 <div class="callout-content">
 <p>Here we see <code>&gt;</code> being used as a shell prompt, whereas
@@ -3934,19 +3934,19 @@ <h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb5-2"><a href="#cb5-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb5-3"><a href="#cb5-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb5-4"><a href="#cb5-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>or:</p>
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb6-4"><a href="#cb6-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb6-2"><a href="#cb6-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb6-3"><a href="#cb6-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb6-4"><a href="#cb6-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>it would work exactly the same way. <em>Don’t do this.</em> Programs
 are only useful if people can understand them, so meaningless names
@@ -3977,15 +3977,15 @@ <h3 class="callout-title">Write your own loop<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
-<span id="cb7-2"><a href="#cb7-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb7-3"><a href="#cb7-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
-<span id="cb7-4"><a href="#cb7-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
+<span id="cb7-2"><a href="#cb7-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb7-3"><a href="#cb7-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
+<span id="cb7-4"><a href="#cb7-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4025,19 +4025,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
-<span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb10-2"><a href="#cb10-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb10-3"><a href="#cb10-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
+<span id="cb10-4"><a href="#cb10-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Now, what is the output of the following code?</p>
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
-<span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Why do these two loops give different outputs?</p>
 </div>
@@ -4048,7 +4048,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The first code block gives the same output on each iteration through
 the loop. Bash expands the wildcard <code>*.pdb</code> within the loop
@@ -4058,10 +4058,10 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb12-3"><a href="#cb12-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-4"><a href="#cb12-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb12-3"><a href="#cb12-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-4"><a href="#cb12-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4103,10 +4103,10 @@ <h3 class="callout-title">Limiting Sets of Files<a class="anchor" aria-label="an
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
-<span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb15-3"><a href="#cb15-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb15-4"><a href="#cb15-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
+<span id="cb15-2"><a href="#cb15-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb15-3"><a href="#cb15-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb15-4"><a href="#cb15-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>No files are listed.</li>
@@ -4123,7 +4123,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so any file name starting with the letter c, followed by
@@ -4144,10 +4144,10 @@ <h3 class="callout-title">Limiting Sets of Files<em>(continued)</em><a class="an
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
-<span id="cb16-2"><a href="#cb16-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb16-3"><a href="#cb16-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb16-4"><a href="#cb16-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
+<span id="cb16-2"><a href="#cb16-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb16-3"><a href="#cb16-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb16-4"><a href="#cb16-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>The same files would be listed.</li>
@@ -4165,7 +4165,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so a file name with zero or more characters before a letter
@@ -4187,11 +4187,11 @@ <h3 class="callout-title">Saving to a File in a Loop - Part One<a class="anchor"
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb17-2"><a href="#cb17-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb17-3"><a href="#cb17-3" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
-<span id="cb17-4"><a href="#cb17-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
-<span id="cb17-5"><a href="#cb17-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb17-2"><a href="#cb17-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb17-3"><a href="#cb17-3" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
+<span id="cb17-4"><a href="#cb17-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
+<span id="cb17-5"><a href="#cb17-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>Prints <code>cubane.pdb</code>, <code>ethane.pdb</code>,
@@ -4216,7 +4216,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li>The text from each file in turn gets written to the
@@ -4241,10 +4241,10 @@ <h3 class="callout-title">Saving to a File in a Loop - Part Two<a class="anchor"
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb18-4"><a href="#cb18-4" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb18-4"><a href="#cb18-4" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>All of the text from <code>cubane.pdb</code>,
@@ -4272,7 +4272,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>3 is the correct answer. <code>&gt;&gt;</code> appends to a file,
 rather than overwriting it with the redirected output from a command.
@@ -4288,11 +4288,11 @@ <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb19-2"><a href="#cb19-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb19-3"><a href="#cb19-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb19-4"><a href="#cb19-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb19-5"><a href="#cb19-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb19-2"><a href="#cb19-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb19-3"><a href="#cb19-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb19-4"><a href="#cb19-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb19-5"><a href="#cb19-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>The shell starts by expanding <code>*.dat</code> to create the list
 of files it will process. The <strong>loop body</strong> then executes
@@ -4302,7 +4302,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
 </div>
 <p>prints:</p>
 <div class="codewrapper">
@@ -4316,11 +4316,11 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb22-2"><a href="#cb22-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb22-3"><a href="#cb22-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
-<span id="cb22-4"><a href="#cb22-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb22-5"><a href="#cb22-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb22-2"><a href="#cb22-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb22-3"><a href="#cb22-3" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
+<span id="cb22-4"><a href="#cb22-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb22-5"><a href="#cb22-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>because then the first time through the loop, when
 <code>$filename</code> expanded to <code>basilisk.dat</code>, the shell
@@ -4328,12 +4328,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <code>head</code> and <code>tail</code> combination selects lines 81-100
 from whatever file is being processed (assuming the file has at least
 100 lines).</p>
-<div id="spaces-in-names" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="spaces-in-names" class="callout-inner">
-<h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="spaces-in-names">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a>
 </h3>
 <div class="callout-content">
 <p>Spaces are used to separate the elements of the list that we are
@@ -4347,10 +4347,10 @@ <h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
-<span id="cb24-2"><a href="#cb24-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb24-3"><a href="#cb24-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb24-4"><a href="#cb24-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
+<span id="cb24-2"><a href="#cb24-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb24-3"><a href="#cb24-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb24-4"><a href="#cb24-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>It is simpler to avoid using spaces (or other special characters) in
 filenames.</p>
@@ -4390,13 +4390,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>because that would expand to:</p>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>This wouldn’t back up our files, instead we get an error:</p>
 <div class="codewrapper">
@@ -4413,10 +4413,10 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb30-2"><a href="#cb30-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb30-3"><a href="#cb30-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
-<span id="cb30-4"><a href="#cb30-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb30-2"><a href="#cb30-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb30-3"><a href="#cb30-3" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
+<span id="cb30-4"><a href="#cb30-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>This loop runs the <code>cp</code> command once for each filename.
 The first time, when <code>$filename</code> expands to
@@ -4424,19 +4424,19 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
 </div>
 <p>The second time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
 </div>
 <p>The third and last time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
 </div>
 <p>Since the <code>cp</code> command does not normally produce any
 output, it’s hard to check that the loop is working correctly. However,
@@ -4466,12 +4466,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4490,10 +4490,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb36-3"><a href="#cb36-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb36-4"><a href="#cb36-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb36-3"><a href="#cb36-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb36-4"><a href="#cb36-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4516,14 +4516,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>Using the <kbd>←</kbd>, Nelle navigates to the <code>echo</code>
 command and changes it to <code>bash goostats.sh</code>:</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>When she presses <kbd>Enter</kbd>, the shell runs the modified
 command. However, nothing appears to happen — there is no output. After
@@ -4535,15 +4535,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
-<div id="beginning-and-end" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="beginning-and-end" class="callout-inner">
-<h3 class="callout-title">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="beginning-and-end">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a>
 </h3>
 <div class="callout-content">
 <p>We can move to the beginning of a line in the shell by typing
@@ -4568,12 +4568,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <code>cat stats-NENE01729B.txt</code> to examine one of the output
 files. It looks good, so she decides to get some coffee and catch up on
 her reading.</p>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout-inner">
-<h3 class="callout-title">Those Who Know History Can Choose to Repeat
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="those-who-know-history-can-choose-to-repeat-it">Those Who Know History Can Choose to Repeat
 It<a class="anchor" aria-label="anchor" href="#those-who-know-history-can-choose-to-repeat-it"></a>
 </h3>
 <div class="callout-content">
@@ -4585,7 +4585,7 @@ <h3 class="callout-title">Those Who Know History Can Choose to Repeat
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4602,12 +4602,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 </div>
 </div>
-<div id="other-history-commands" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-history-commands" class="callout-inner">
-<h3 class="callout-title">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-history-commands">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a>
 </h3>
 <div class="callout-content">
 <p>There are a number of other shortcut commands for getting at the
@@ -4651,30 +4651,30 @@ <h3 class="callout-title">Doing a Dry Run<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb44-2"><a href="#cb44-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb44-3"><a href="#cb44-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb44-4"><a href="#cb44-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb44-2"><a href="#cb44-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb44-3"><a href="#cb44-3" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb44-4"><a href="#cb44-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>What is the difference between the two loops below, and which one
 would we want to run?</p>
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 1</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Version 1</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 2</span></span>
-<span id="cb46-2"><a href="#cb46-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb46-3"><a href="#cb46-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb46-4"><a href="#cb46-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
-<span id="cb46-5"><a href="#cb46-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="co"># Version 2</span></span>
+<span id="cb46-2"><a href="#cb46-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb46-3"><a href="#cb46-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb46-4"><a href="#cb46-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
+<span id="cb46-5"><a href="#cb46-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -4684,7 +4684,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The second version is the one we want to run. This prints to screen
 everything enclosed in the quote marks, expanding the loop variable name
@@ -4717,13 +4717,13 @@ <h3 class="callout-title">Nested Loops<a class="anchor" aria-label="anchor" href
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
-<span id="cb47-2"><a href="#cb47-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb47-3"><a href="#cb47-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
-<span id="cb47-4"><a href="#cb47-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
-<span id="cb47-5"><a href="#cb47-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
-<span id="cb47-6"><a href="#cb47-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
-<span id="cb47-7"><a href="#cb47-7" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
+<span id="cb47-2"><a href="#cb47-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb47-3"><a href="#cb47-3" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
+<span id="cb47-4"><a href="#cb47-4" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
+<span id="cb47-5"><a href="#cb47-5" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
+<span id="cb47-6"><a href="#cb47-6" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
+<span id="cb47-7"><a href="#cb47-7" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -4733,7 +4733,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <p>We have a nested loop, i.e. contained within another loop, so for
 each species in the outer loop, the inner loop (the nested loop)
@@ -4832,8 +4832,8 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>The command <code>nano middle.sh</code> opens the file
 <code>middle.sh</code> within the text editor ‘nano’ (which runs within
@@ -4855,7 +4855,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4868,12 +4868,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Sure enough, our script’s output is exactly what we would get if we
 ran that pipeline directly.</p>
-<div id="text-vs.-whatever" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="text-vs.-whatever" class="callout-inner">
-<h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs.-whatever"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="text-vs--whatever">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs--whatever"></a>
 </h3>
 <div class="callout-content">
 <p>We usually call programs like Microsoft Word or LibreOffice Writer
@@ -4897,7 +4897,7 @@ <h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>Now, within “nano”, replace the text <code>octane.pdb</code> with the
 special variable called <code>$1</code>:</p>
@@ -4908,7 +4908,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4923,7 +4923,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4934,12 +4934,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 ATOM     12  H           1      -0.048  -1.362  -0.205  1.00  0.00
 ATOM     13  H           1      -1.183   0.500  -1.412  1.00  0.00</code></pre>
 </div>
-<div id="double-quotes-around-arguments" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="double-quotes-around-arguments" class="callout-inner">
-<h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="double-quotes-around-arguments">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a>
 </h3>
 <div class="callout-content">
 <p>For the same reason that we put the loop variable inside
@@ -4961,14 +4961,14 @@ <h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code>head -n "$2" "$1" | tail -n "$3"</code></pre>
 <p>We can now run:</p>
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4984,7 +4984,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5002,7 +5002,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code># Select lines from the middle of a file.
 # Usage: bash middle.sh filename end_line num_lines
@@ -5019,7 +5019,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <p>because <code>wc -l</code> lists the number of lines in the files
 (recall that <code>wc</code> stands for ‘word count’, adding the
@@ -5039,7 +5039,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
 </div>
 <pre class="source"><code># Sort files by their length.
 # Usage: bash sorted.sh one_or_more_filenames
@@ -5047,7 +5047,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5100,21 +5100,21 @@ <h3 class="callout-title">List Unique Species<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
-<span id="cb25-2"><a href="#cb25-2" aria-hidden="true" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
-<span id="cb25-3"><a href="#cb25-3" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb25-4"><a href="#cb25-4" aria-hidden="true" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
-<span id="cb25-5"><a href="#cb25-5" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
-<span id="cb25-6"><a href="#cb25-6" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb25-7"><a href="#cb25-7" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
-<span id="cb25-8"><a href="#cb25-8" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
-<span id="cb25-9"><a href="#cb25-9" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
-<span id="cb25-10"><a href="#cb25-10" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
+<span id="cb25-2"><a href="#cb25-2" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
+<span id="cb25-3"><a href="#cb25-3" tabindex="-1"></a></span>
+<span id="cb25-4"><a href="#cb25-4" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
+<span id="cb25-5"><a href="#cb25-5" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
+<span id="cb25-6"><a href="#cb25-6" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb25-7"><a href="#cb25-7" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
+<span id="cb25-8"><a href="#cb25-8" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
+<span id="cb25-9"><a href="#cb25-9" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
+<span id="cb25-10"><a href="#cb25-10" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -5128,7 +5128,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
 </div>
 <p>The file <code>redo-figure-3.sh</code> now contains:</p>
 <pre class="source"><code>297 bash goostats.sh NENE01729B.txt stats-NENE01729B.txt
@@ -5153,7 +5153,7 @@ <h3 class="callout-title">Why Record Commands in the History Before
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
 </div>
 <p>the last command in the file is the <code>history</code> command
 itself, i.e., the shell has added <code>history</code> to the command
@@ -5168,7 +5168,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>If a command causes something to crash or hang, it might be useful to
 know what that command was, in order to investigate the problem. Were
@@ -5194,37 +5194,37 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
 </div>
 <p>She creates a file using <code>nano</code> …</p>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
 </div>
 <p>…which contains the following:</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb31-3"><a href="#cb31-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb31-4"><a href="#cb31-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb31-5"><a href="#cb31-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb31-6"><a href="#cb31-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb31-3"><a href="#cb31-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb31-4"><a href="#cb31-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb31-5"><a href="#cb31-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb31-6"><a href="#cb31-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>She saves this in a file called <code>do-stats.sh</code> so that she
 can now re-do the first stage of her analysis by typing:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>She can also do this:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
 </div>
 <p>so that the output is just the number of files processed rather than
 the names of the files that were processed.</p>
@@ -5234,12 +5234,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>The advantage is that this always selects the right files: she
 doesn’t have to remember to exclude the ‘Z’ files. The disadvantage is
@@ -5264,15 +5264,15 @@ <h3 class="callout-title">Variables in Shell Scripts<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
-<span id="cb35-2"><a href="#cb35-2" aria-hidden="true" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
+<span id="cb35-2"><a href="#cb35-2" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
 </div>
 <p>While you are in the <code>alkanes</code> directory, you type the
 following command:</p>
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
 </div>
 <p>Which of the following outputs would you expect to see?</p>
 <ol style="list-style-type: decimal">
@@ -5293,7 +5293,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The correct answer is 2.</p>
 <p>The special variables <code>$1</code>, <code>$2</code> and
@@ -5302,8 +5302,8 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
-<span id="cb37-2"><a href="#cb37-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
+<span id="cb37-2"><a href="#cb37-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
 </div>
 <p>The shell does not expand <code>'*.pdb'</code> because it is enclosed
 by quote marks. As such, the first argument to the script is
@@ -5329,7 +5329,7 @@ <h3 class="callout-title">Find the Longest File With a Given
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
 </div>
 <p>would print the name of the <code>.pdb</code> file in
 <code>shell-lesson-data/exercise-data/alkanes</code> that has the most
@@ -5338,7 +5338,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -5348,18 +5348,18 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
-<span id="cb40-3"><a href="#cb40-3" aria-hidden="true" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
-<span id="cb40-4"><a href="#cb40-4" aria-hidden="true" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
-<span id="cb40-5"><a href="#cb40-5" aria-hidden="true" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
-<span id="cb40-6"><a href="#cb40-6" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb40-7"><a href="#cb40-7" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
+<span id="cb40-3"><a href="#cb40-3" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
+<span id="cb40-4"><a href="#cb40-4" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
+<span id="cb40-5"><a href="#cb40-5" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
+<span id="cb40-6"><a href="#cb40-6" tabindex="-1"></a></span>
+<span id="cb40-7"><a href="#cb40-7" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <p>The first part of the pipeline, <code>wc -l $1/*.$2 | sort -n</code>,
 counts the lines in each file and sorts them numerically (largest last).
@@ -5392,23 +5392,23 @@ <h3 class="callout-title">Script Reading Comprehension<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 1</span></span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="co"># Script 1</span></span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 2</span></span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
-<span id="cb42-3"><a href="#cb42-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb42-4"><a href="#cb42-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
-<span id="cb42-5"><a href="#cb42-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="co"># Script 2</span></span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
+<span id="cb42-3"><a href="#cb42-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb42-4"><a href="#cb42-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
+<span id="cb42-5"><a href="#cb42-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 3</span></span>
-<span id="cb43-2"><a href="#cb43-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="co"># Script 3</span></span>
+<span id="cb43-2"><a href="#cb43-2" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
 </div>
 </div>
 </div>
@@ -5418,7 +5418,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solutions</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>In each case, the shell expands the wildcard in <code>*.pdb</code>
 before passing the resulting list of file names as arguments to the
@@ -5456,26 +5456,26 @@ <h3 class="callout-title">Debugging Scripts<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb45-6"><a href="#cb45-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb45-6"><a href="#cb45-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>When you run it from the <code>north-pacific-gyre</code>
 directory:</p>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>the output is blank. To figure out why, re-run the script using the
 <code>-x</code> option:</p>
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>What is the output showing you? Which line is responsible for the
 error?</p>
@@ -5487,7 +5487,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>The <code>-x</code> option causes <code>bash</code> to run in debug
 mode. This prints out each command as it is run, which will help you to
@@ -5584,9 +5584,9 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
-<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
+<span id="cb1-3"><a href="#cb1-3" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5607,7 +5607,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5630,7 +5630,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5649,7 +5649,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5663,7 +5663,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5680,7 +5680,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5698,7 +5698,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5711,7 +5711,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5726,7 +5726,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5749,7 +5749,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5764,7 +5764,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5817,7 +5817,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The correct answer is 3, because the <code>-w</code> option looks
 only for whole-word matches. The other options will also match ‘of’ when
@@ -5826,12 +5826,12 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="wildcards" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
 </h3>
 <div class="callout-content">
 <p><code>grep</code>‘s real power doesn’t come from its options, though;
@@ -5845,7 +5845,7 @@ <h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5896,13 +5896,13 @@ <h3 class="callout-title">Tracking a Species<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span></span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-6"><a href="#cb28-6" aria-hidden="true" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
-<span id="cb28-7"><a href="#cb28-7" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a><span class="op">&gt;</span></span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-6"><a href="#cb28-6" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
+<span id="cb28-7"><a href="#cb28-7" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
 </div>
 <p>Hint: use <code>man grep</code> to look for how to grep text
 recursively in a directory and <code>man cut</code> to select more than
@@ -5917,7 +5917,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <pre class="source"><code>grep -w $1 -r $2 | cut -d : -f 2 | cut -d , -f 1,3 &gt; $1.txt</code></pre>
 <p>Actually, you can swap the order of the two cut commands and it still
@@ -5928,7 +5928,7 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
 </div>
 </div>
 </div>
@@ -5965,7 +5965,7 @@ <h3 class="callout-title">Little Women<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solutions</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <pre class="source"><code>for sis in Jo Meg Beth Amy
 do
@@ -6028,7 +6028,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6064,7 +6064,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6081,7 +6081,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6104,7 +6104,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6119,7 +6119,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
 </div>
 <p><code>find</code> did what we asked; we just asked for the wrong
 thing.</p>
@@ -6131,7 +6131,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6140,12 +6140,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <span><span class="va">.</span><span class="op">/</span><span class="va">writing</span><span class="op">/</span><span class="va">haiku.txt</span></span>
 <span><span class="va">.</span><span class="op">/</span><span class="va">numbers.txt</span></span></code></pre>
 </div>
-<div id="listing-vs.-finding" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="listing-vs.-finding" class="callout-inner">
-<h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs.-finding"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="listing-vs--finding">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs--finding"></a>
 </h3>
 <div class="callout-content">
 <p><code>ls</code> and <code>find</code> can be made to do similar
@@ -6165,7 +6165,7 @@ <h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6185,7 +6185,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
 </div>
 <p>which is what we wanted. This expansion is exactly what the shell
 does when it expands wildcards like <code>*</code> and <code>?</code>,
@@ -6199,7 +6199,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6235,7 +6235,7 @@ <h3 class="callout-title">Matching and Subtracting<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>Option 1 is correct. Putting the match expression in quotes prevents
 the shell expanding it, so it gets passed to the <code>find</code>
@@ -6251,12 +6251,12 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="binary-files" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="binary-files" class="callout-inner">
-<h3 class="callout-title">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="binary-files">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a>
 </h3>
 <div class="callout-content">
 <p>We have focused exclusively on finding patterns in text files. What
@@ -6302,7 +6302,7 @@ <h3 class="callout-title">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -6312,7 +6312,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>Find all files with a <code>.dat</code> extension recursively
@@ -6398,8 +6398,8 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://swcarpentry.github.io/shell-novice/aio.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/aio.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/discuss.html b/discuss.html
index 29b4f2baf..e70e23d48 100644
--- a/discuss.html
+++ b/discuss.html
@@ -389,7 +389,7 @@ <h1>Discussion</h1>
   "identifier": "https://swcarpentry.github.io/shell-novice/discuss.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/images.html b/images.html
index 04495f730..b52329d0d 100644
--- a/images.html
+++ b/images.html
@@ -390,8 +390,8 @@ <h3 id="05-loop-figure-1">Figure 1</h3>
   "url": "https://swcarpentry.github.io/shell-novice/images.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/images.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/index.html b/index.html
index 7b7459545..e8f79a1d9 100644
--- a/index.html
+++ b/index.html
@@ -316,14 +316,13 @@ <h3 class="callout-title">Prerequisites<a class="anchor" aria-label="anchor" hre
 folder as your working directory.</li>
 </ol><p>In the lesson, you will find out how to access the data files in this
 folder.</p>
-<div id="where-to-type-commands-how-to-open-a-new-shell" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="where-to-type-commands-how-to-open-a-new-shell" class="callout-inner">
-<h3 class="callout-title">Where to type commands: How to open a new
-shell<a class="anchor" aria-label="anchor" href="#where-to-type-commands-how-to-open-a-new-shell"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="where-to-type-commands-how-to-open-a-new-shell">Where to type commands: How to open a new
+shell<a class="anchor" aria-label="anchor" href="#where-to-type-commands-how-to-open-a-new-shell"></a></h3>
 <div class="callout-content">
 <p>The shell is a program that enables us to send commands to the
 computer and receive output. It is also referred to as the terminal or
@@ -456,8 +455,8 @@ <h4 class="accordion-header" id="headingSolution3">Linux</h4>
   "url": "https://swcarpentry.github.io/shell-novice/index.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/index.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor-notes.html b/instructor-notes.html
index 8a4926585..7669076f6 100644
--- a/instructor-notes.html
+++ b/instructor-notes.html
@@ -488,7 +488,7 @@ <h1>Instructor Notes</h1>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="va">PS1</span><span class="op">=</span><span class="st">'$ '</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="va">PS1</span><span class="op">=</span><span class="st">'$ '</span></span></code></pre>
 </div>
 </li>
 <li><p>On Windows machines if <code>nano</code> hasn’t been properly
@@ -503,8 +503,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb2-2"><a href="#cb2-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span></code></pre>
 </div>
 <p>will always put someone on their desktop (unless their machine is
 backed up using enterprise OneDrive, see next point). Have them create
@@ -521,8 +521,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"~/OneDrive - Name Of Enterprise/Desktop"</span></span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"C:/Users/Username/OneDrive - Name Of Enterprise/Desktop"</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"~/OneDrive - Name Of Enterprise/Desktop"</span></span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"C:/Users/Username/OneDrive - Name Of Enterprise/Desktop"</span></span></code></pre>
 </div>
 <p>One way to spot if the computer is using this kind of configuration
 is to look at files, folders or links on the desktop. Usually the icon
@@ -623,8 +623,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
   "url": "https://swcarpentry.github.io/shell-novice/instructor-notes.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor-notes.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/01-intro.html b/instructor/01-intro.html
index 0bfa67f84..d1d53d926 100644
--- a/instructor/01-intro.html
+++ b/instructor/01-intro.html
@@ -362,7 +362,7 @@ <h3 id="the-shell">The Shell<a class="anchor" aria-label="anchor" href="#the-she
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
 </div>
 <p>The shell typically uses <code>$</code> as the prompt, but may use a
 different symbol. In the examples for this lesson, we’ll show the prompt
@@ -382,7 +382,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
 </div>
 <p>The prompt might even include more than this. Do not worry if your
 prompt is not just a short <code>$</code>. This lesson does not depend
@@ -395,7 +395,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -403,20 +403,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="output" tabindex="0"><code>Desktop     Downloads   Movies      Pictures
 Documents   Library     Music       Public</code></pre>
 </div>
-<div id="command-not-found" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="command-not-found" class="callout-inner">
-<h3 class="callout-title">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="command-not-found">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a></h3>
 <div class="callout-content">
 <p>If the shell can’t find a program whose name is the command you
 typed, it will print an error message such as:</p>
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -542,7 +541,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/01-intro.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/02-filedir.html b/instructor/02-filedir.html
index b44540357..34e32aec1 100644
--- a/instructor/02-filedir.html
+++ b/instructor/02-filedir.html
@@ -320,7 +320,7 @@ <h3 class="card-title">Objectives</h3>
   <h3 class="accordion-header" id="headingInstructor1">
 <div class="note-square"><i aria-hidden="true" class="callout-icon" data-feather="edit-2"></i></div>Instructor Note</h3>
 </button>
-<div id="collapseInstructor1" class="accordion-collapse collapse" data-bs-parent="#accordionInstructor1" aria-labelledby="headingInstructor1">
+<div id="collapseInstructor1" class="accordion-collapse collapse" aria-labelledby="headingInstructor1" data-bs-parent="#accordionInstructor1">
 <div class="accordion-body">
 <p>Introducing and navigating the filesystem in the shell (covered in <a href="02-filedir.html">Navigating Files and Directories</a> section) can
 be confusing. You may have both terminal and GUI file explorer open side
@@ -348,7 +348,7 @@ <h3 class="accordion-header" id="headingInstructor1">
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -357,13 +357,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Here, the computer’s response is <code>/Users/nelle</code>, which is
 Nelle’s <strong>home directory</strong>:</p>
-<div id="home-directory-variation" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="home-directory-variation" class="callout-inner">
-<h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="home-directory-variation">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a></h3>
 <div class="callout-content">
 <p>The home directory path will look different on different operating
 systems. On Linux, it may look like <code>/home/nelle</code>, and on
@@ -402,13 +401,12 @@ <h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="
 first part of its name. Similarly, we know that <code>/Users</code> is
 stored inside the root directory <code>/</code> because its name begins
 with <code>/</code>.</p>
-<div id="slashes" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="slashes" class="callout-inner">
-<h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="slashes">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a></h3>
 <div class="callout-content">
 <p>Notice that there are two meanings for the <code>/</code> character.
 When it appears at the front of a file or directory name, it refers to
@@ -433,7 +431,7 @@ <h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#sl
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -458,7 +456,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -470,13 +468,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <strong>sub-directories</strong>. Any names in the output that don’t
 have a classification symbol are <strong>files</strong> in the current
 working directory.</p>
-<div id="clearing-your-terminal" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="clearing-your-terminal" class="callout-inner">
-<h3 class="callout-title">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="clearing-your-terminal">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a></h3>
 <div class="callout-content">
 <p>If your screen gets too cluttered, you can clear your terminal using
 the <code>clear</code> command. You can still access previous commands
@@ -496,23 +493,22 @@ <h3 id="getting-help">Getting help<a class="anchor" aria-label="anchor" href="#g
 </ol><div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <ol start="2" style="list-style-type: decimal"><li>We can read its manual with <code>man</code> (available on Linux and
 macOS):</li>
 </ol><div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>We’ll describe both ways next.</p>
-<div id="help-for-built-in-commands" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="help-for-built-in-commands" class="callout-inner">
-<h3 class="callout-title">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="help-for-built-in-commands">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a></h3>
 <div class="callout-content">
 <p>Some commands are built in to the Bash shell, rather than existing as
 separate programs on the filesystem. One example is the <code>cd</code>
@@ -531,7 +527,7 @@ <h4 id="the---help-option">The <code>--help</code> option<a class="anchor" aria-
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -562,20 +558,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   -F, --classify             append indicator (one of */=&gt;@|) to entries
 ...        ...        ...</code></pre>
 </div>
-<div id="unsupported-command-line-options" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="unsupported-command-line-options" class="callout-inner">
-<h3 class="callout-title">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="unsupported-command-line-options">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a></h3>
 <div class="callout-content">
 <p>If you try to use an option that is not supported, <code>ls</code>
 and other commands will usually print an error message similar to:</p>
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -593,7 +588,7 @@ <h4 id="the-man-command">The <code>man</code> command<a class="anchor" aria-labe
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>This command will turn your terminal into a page with a description
 of the <code>ls</code> command and its options.</p>
@@ -607,13 +602,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <kbd>Shift</kbd>+<kbd>N</kbd> (for moving backward).</p>
 <p>To <strong>quit</strong> the <code>man</code> pages, press
 <kbd>Q</kbd>.</p>
-<div id="manual-pages-on-the-web" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="manual-pages-on-the-web" class="callout-inner">
-<h3 class="callout-title">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="manual-pages-on-the-web">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a></h3>
 <div class="callout-content">
 <p>Of course, there is a third way to access help for commands:
 searching the internet via your web browser. When using internet search,
@@ -648,7 +642,7 @@ <h3 class="callout-title">Exploring More<code>ls</code>Options<a class="anchor"
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>-l</code> option makes <code>ls</code> use a
 <strong>l</strong>ong listing format, showing not only the
@@ -684,7 +678,7 @@ <h3 class="callout-title">Listing in Reverse Chronological Order<a class="anchor
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The most recently changed file is listed last when using
 <code>-rt</code>. This can be very useful for finding your most recent
@@ -708,7 +702,7 @@ <h3 id="exploring-other-directories">Exploring Other Directories<a class="anchor
 <div class="codewrapper sourceCode" id="cb14">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -739,7 +733,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -761,9 +755,9 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
 </div>
 <p>These commands will move us from our home directory into our Desktop
 directory, then into the <code>shell-lesson-data</code> directory, then
@@ -780,7 +774,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -790,7 +784,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -803,7 +797,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb23">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -820,7 +814,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
 </div>
 <p><code>..</code> is a special directory name meaning “the directory
 containing this one”, or more succinctly, the <strong>parent</strong> of
@@ -830,7 +824,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -843,7 +837,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -861,13 +855,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>Note that in most command line tools, multiple options can be
 combined with a single <code>-</code> and no spaces between the options;
 <code>ls -F -a</code> is equivalent to <code>ls -Fa</code>.</p>
-<div id="other-hidden-files" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-hidden-files" class="callout-inner">
-<h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-hidden-files">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a></h3>
 <div class="callout-content">
 <p>In addition to the hidden directories <code>..</code> and
 <code>.</code>, you may also see a file called
@@ -889,14 +882,14 @@ <h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
 </div>
 <p>How can you check what happened? <code>pwd</code> gives us the
 answer!</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -913,7 +906,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
 </div>
 <p>Check that we’ve moved to the right place by running <code>pwd</code>
 and <code>ls -F</code>.</p>
@@ -939,7 +932,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -949,17 +942,16 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Run <code>pwd</code> and <code>ls -F</code> to ensure that we’re in
 the directory we expect.</p>
-<div id="two-more-shortcuts" class="callout callout">
+<div id="callout8" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-more-shortcuts" class="callout-inner">
-<h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-more-shortcuts">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a></h3>
 <div class="callout-content">
 <p>The shell interprets a tilde (<code>~</code>) character at the start
 of a path to mean “the current user’s home directory”. For example, if
@@ -982,20 +974,20 @@ <h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Then <code>cd</code> into the <code>exercise-data/creatures</code>
 directory</p>
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
 </div>
 <p>Now if you run</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
 </div>
 <p>you’ll see you’re back in <code>~/Desktop/shell-lesson-data</code>.
 Run <code>cd -</code> again and you’re back in
@@ -1031,7 +1023,7 @@ <h3 class="callout-title">Absolute vs Relative Paths<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>No: <code>.</code> stands for the current directory.</p></li>
 <li><p>No: <code>/</code> stands for the root directory.</p></li>
@@ -1072,7 +1064,7 @@ <h3 class="callout-title">Relative Path Resolution<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>No: there <em>is</em> a directory <code>backup</code> in
 <code>/Users</code>.</p></li>
@@ -1114,7 +1106,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>No: <code>pwd</code> is not the name of a directory.</p></li>
 <li><p>Yes: <code>ls</code> without directory argument lists files and
@@ -1134,7 +1126,7 @@ <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <figure><img src="../fig/shell_command_syntax.svg" alt="General syntax of a shell command" class="figure mx-auto d-block"></figure><p><code>ls</code> is the <strong>command</strong>, with an
 <strong>option</strong> <code>-F</code> and an <strong>argument</strong>
@@ -1160,8 +1152,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1176,7 +1168,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1190,7 +1182,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1199,13 +1191,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 Library/              Users/
 Network/              Volumes/</code></pre>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout callout">
+<div id="callout9" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout-inner">
-<h3 class="callout-title">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="when-to-use-short-or-long-options">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a></h3>
 <div class="callout-content">
 <p>When options exist as both short and long options:</p>
 <ul><li>Use the short option when typing commands directly into the shell to
@@ -1235,7 +1226,7 @@ <h3 id="nelles-pipeline-organizing-files">Nelle’s Pipeline: Organizing Files<a
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>This command is a lot to type, but she can let the shell do most of
 the work through what is called <strong>tab completion</strong>. If she
@@ -1243,14 +1234,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
 </div>
 <p>and then presses <kbd>Tab</kbd> (the tab key on her keyboard), the
 shell automatically completes the directory name for her:</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>Pressing <kbd>Tab</kbd> again does nothing, since there are multiple
 possibilities; pressing <kbd>Tab</kbd> twice brings up a list of all the
@@ -1261,15 +1252,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb51">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
 </div>
 <p>To see all of those files, she can press <kbd>Tab</kbd> twice
 more.</p>
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
-<span id="cb52-2"><a href="#cb52-2" aria-hidden="true" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
+<span id="cb52-2"><a href="#cb52-2" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
 </div>
 <p>This is called <strong>tab completion</strong>, and we will see it in
 many other tools as we go on.</p>
@@ -1372,7 +1363,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/02-filedir.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/03-create.html b/instructor/03-create.html
index 5a2000f81..7d2d32dc8 100644
--- a/instructor/03-create.html
+++ b/instructor/03-create.html
@@ -325,7 +325,7 @@ <h3 id="step-one-see-where-we-are-and-what-we-already-have">Step one: see where
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -337,8 +337,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -353,7 +353,7 @@ <h3 id="create-a-directory">Create a directory<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
 </div>
 <p>As you might guess from its name, <code>mkdir</code> means ‘make
 directory’. Since <code>thesis</code> is a relative path (i.e., does not
@@ -362,7 +362,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -374,7 +374,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
 </div>
 <p>Note that <code>mkdir</code> is not limited to creating single
 directories one at a time. The <code>-p</code> option allows
@@ -383,7 +383,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
 </div>
 <p>The <code>-R</code> option to the <code>ls</code> command will list
 all nested subdirectories within a directory. Let’s use
@@ -392,7 +392,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -404,13 +404,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 
 ../project/results:</code></pre>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout-inner">
-<h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-ways-of-doing-the-same-thing">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a></h3>
 <div class="callout-content">
 <p>Using the shell to create a directory is no different than using a
 file explorer. If you open the current directory using your operating
@@ -421,13 +420,12 @@ <h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria
 </div>
 </div>
 </div>
-<div id="good-names-for-files-and-directories" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="good-names-for-files-and-directories" class="callout-inner">
-<h3 class="callout-title">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="good-names-for-files-and-directories">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a></h3>
 <div class="callout-content">
 <p>Complicated names of files and directories can make your life painful
 when working on the command line. Here we provide a few useful tips for
@@ -460,7 +458,7 @@ <h3 class="callout-title">Good names for files and directories<a class="anchor"
   <h3 class="accordion-header" id="headingInstructor1">
 <div class="note-square"><i aria-hidden="true" class="callout-icon" data-feather="edit-2"></i></div>Instructor Note</h3>
 </button>
-<div id="collapseInstructor1" class="accordion-collapse collapse" data-bs-parent="#accordionInstructor1" aria-labelledby="headingInstructor1">
+<div id="collapseInstructor1" class="accordion-collapse collapse" aria-labelledby="headingInstructor1" data-bs-parent="#accordionInstructor1">
 <div class="accordion-body">
 <p>Learners can sometimes get trapped within command-line text editors
 such as Vim, Emacs, or Nano. Closing the terminal emulator and opening a
@@ -481,16 +479,15 @@ <h3 id="create-a-text-file">Create a text file<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
 </div>
-<div id="which-editor" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="which-editor" class="callout-inner">
-<h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="which-editor">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a></h3>
 <div class="callout-content">
 <p>When we say, ‘<code>nano</code> is a text editor’ we really do mean
 ‘text’. It can only work with plain character data, not tables, images,
@@ -522,13 +519,12 @@ <h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" hre
 to accept the suggested default of <code>draft.txt</code>.</p>
 <p>Once our file is saved, we can use <kbd>Ctrl</kbd>+<kbd>X</kbd> to
 quit the editor and return to the shell.</p>
-<div id="control-ctrl-or-key" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="control-ctrl-or-key" class="callout-inner">
-<h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="control-ctrl-or-key">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a></h3>
 <div class="callout-content">
 <p>The Control key is also called the ‘Ctrl’ key. There are various ways
 in which using the Control key may be described. For example, you may
@@ -553,7 +549,7 @@ <h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="a
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -573,7 +569,7 @@ <h3 class="callout-title">Creating Files a Different Way<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li><p>What did the <code>touch</code> command do? When you look at your
 current directory using the GUI file explorer, does the file show
@@ -589,7 +585,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>The <code>touch</code> command generates a new file called
 <code>my_file.txt</code> in your current directory. You can observe this
@@ -624,18 +620,17 @@ <h3 class="callout-title">Creating Files a Different Way<em>(continued)</em><a c
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
 </div>
 </div>
 </div>
 </div>
-<div id="whats-in-a-name" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="whats-in-a-name" class="callout-inner">
-<h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="whats-in-a-name">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a></h3>
 <div class="callout-content">
 <p>You may have noticed that all of Nelle’s files are named ‘something
 dot something’, and in this part of the lesson, we always used the
@@ -670,7 +665,7 @@ <h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="ancho
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
 </div>
 <p>In our <code>thesis</code> directory we have a file
 <code>draft.txt</code> which isn’t a particularly informative name, so
@@ -679,7 +674,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
 </div>
 <p>The first argument tells <code>mv</code> what we’re ‘moving’, while
 the second is where it’s to go. In this case, we’re moving
@@ -690,7 +685,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
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@@ -715,7 +710,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
 </div>
 <p>The effect is to move the file from the directory it was in to the
 current working directory. <code>ls</code> now shows us that
@@ -723,7 +718,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -736,7 +731,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -751,7 +746,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -773,18 +768,18 @@ <h3 class="callout-title">Moving Files to a new folder<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
 </div>
 <p>Fill in the blanks to move these files to the <code>raw/</code>
 folder (i.e. the one she forgot to put them in)</p>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
 </div>
 </div>
 </div>
@@ -794,12 +789,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
 </div>
 <p>Recall that <code>..</code> refers to the parent directory (i.e. one
 above the current directory) and that <code>.</code> refers to the
@@ -818,8 +813,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -831,14 +826,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
 </div>
 <p>We can check the result by listing the contents of both the
 <code>thesis</code> and <code>thesis_backup</code> directory:</p>
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -856,8 +851,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
 </div>
 <div id="renaming-files" class="callout challenge">
 <div class="callout-square">
@@ -885,7 +880,7 @@ <h3 class="callout-title">Renaming Files<a class="anchor" aria-label="anchor" hr
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li>No. While this would create a file with the correct name, the
 incorrectly named file still exists in the directory and would need to
@@ -912,7 +907,7 @@ <h3 class="callout-title">Moving and Copying<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -922,7 +917,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -932,10 +927,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
-<span id="cb41-3"><a href="#cb41-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
-<span id="cb41-4"><a href="#cb41-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
+<span id="cb41-3"><a href="#cb41-3" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
+<span id="cb41-4"><a href="#cb41-4" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li><code>proteins-saved.dat recombined</code></li>
 <li><code>recombined</code></li>
@@ -949,7 +944,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We start in the <code>/Users/jamie/data</code> directory, and create
 a new folder called <code>recombined</code>. The second line moves
@@ -985,26 +980,25 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
 </div>
 <p>We can confirm the file has gone using <code>ls</code>:</p>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
 <pre class="error" tabindex="0"><code>ls: cannot access 'quotes.txt': No such file or directory</code></pre>
 </div>
-<div id="deleting-is-forever" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="deleting-is-forever" class="callout-inner">
-<h3 class="callout-title">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="deleting-is-forever">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a></h3>
 <div class="callout-content">
 <p>The Unix shell doesn’t have a trash bin that we can recover deleted
 files from (though most graphical interfaces to Unix do). Instead, when
@@ -1035,7 +1029,7 @@ <h3 class="callout-title">Using<code>rm</code>Safely<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1057,7 +1051,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1072,7 +1066,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
 </div>
 <p>Given that there is no way to retrieve files deleted using the shell,
 <code>rm -r</code> <em>should be used with great caution</em> (you might
@@ -1099,16 +1093,16 @@ <h3 class="callout-title">Copy with Multiple Filenames<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
-<span id="cb49-2"><a href="#cb49-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
+<span id="cb49-2"><a href="#cb49-2" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
 </div>
 <p>In the example below, what does <code>cp</code> do when given three
 or more file names?</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
-<span id="cb50-2"><a href="#cb50-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
+<span id="cb50-2"><a href="#cb50-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1118,7 +1112,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
 </div>
 </div>
 </div>
@@ -1128,7 +1122,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>If given more than one file name followed by a directory name
 (i.e. the destination directory must be the last argument),
@@ -1147,13 +1141,12 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 </div>
 <div class="section level3">
 <h3 id="using-wildcards-for-accessing-multiple-files-at-once">Using wildcards for accessing multiple files at once<a class="anchor" aria-label="anchor" href="#using-wildcards-for-accessing-multiple-files-at-once"></a></h3>
-<div id="wildcards" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a></h3>
 <div class="callout-content">
 <p><code>*</code> is a <strong>wildcard</strong>, which represents zero
 or more other characters. Let’s consider the
@@ -1208,7 +1201,7 @@ <h3 class="callout-title">List filenames matching a pattern<a class="anchor" ari
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The solution is <code>3.</code></p>
 <p><code>1.</code> shows all files whose names contain zero or more
@@ -1244,25 +1237,25 @@ <h3 class="callout-title">More on Wildcards<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb54">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb54-2"><a href="#cb54-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb54-3"><a href="#cb54-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb54-4"><a href="#cb54-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb54-5"><a href="#cb54-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb54-6"><a href="#cb54-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb54-7"><a href="#cb54-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb54-8"><a href="#cb54-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb54-9"><a href="#cb54-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb54-10"><a href="#cb54-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb54-11"><a href="#cb54-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb54-12"><a href="#cb54-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb54-13"><a href="#cb54-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb54-14"><a href="#cb54-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb54-15"><a href="#cb54-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb54-16"><a href="#cb54-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb54-17"><a href="#cb54-17" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb54-18"><a href="#cb54-18" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb54-19"><a href="#cb54-19" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb54-2"><a href="#cb54-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb54-3"><a href="#cb54-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb54-4"><a href="#cb54-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb54-5"><a href="#cb54-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb54-6"><a href="#cb54-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb54-7"><a href="#cb54-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb54-8"><a href="#cb54-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb54-9"><a href="#cb54-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb54-10"><a href="#cb54-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb54-11"><a href="#cb54-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb54-12"><a href="#cb54-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb54-13"><a href="#cb54-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb54-14"><a href="#cb54-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb54-15"><a href="#cb54-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb54-16"><a href="#cb54-16" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb54-17"><a href="#cb54-17" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb54-18"><a href="#cb54-18" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb54-19"><a href="#cb54-19" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
 </div>
 <p>Before heading off to another field trip, she wants to back up her
 data and send some datasets to her colleague Bob. Sam uses the following
@@ -1270,57 +1263,57 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb55">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
-<span id="cb55-2"><a href="#cb55-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
-<span id="cb55-3"><a href="#cb55-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
-<span id="cb55-4"><a href="#cb55-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
+<span id="cb55-2"><a href="#cb55-2" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
+<span id="cb55-3"><a href="#cb55-3" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
+<span id="cb55-4"><a href="#cb55-4" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 <p>Help Sam by filling in the blanks.</p>
 <p>The resulting directory structure should look like this</p>
 <div class="codewrapper sourceCode" id="cb56">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb56-2"><a href="#cb56-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb56-3"><a href="#cb56-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb56-4"><a href="#cb56-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb56-5"><a href="#cb56-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-6"><a href="#cb56-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb56-7"><a href="#cb56-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb56-8"><a href="#cb56-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb56-9"><a href="#cb56-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-10"><a href="#cb56-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-11"><a href="#cb56-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-12"><a href="#cb56-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-13"><a href="#cb56-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-14"><a href="#cb56-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb56-15"><a href="#cb56-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb56-16"><a href="#cb56-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
-<span id="cb56-17"><a href="#cb56-17" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
-<span id="cb56-18"><a href="#cb56-18" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
-<span id="cb56-19"><a href="#cb56-19" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb56-20"><a href="#cb56-20" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-21"><a href="#cb56-21" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-22"><a href="#cb56-22" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-23"><a href="#cb56-23" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
-<span id="cb56-24"><a href="#cb56-24" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
-<span id="cb56-25"><a href="#cb56-25" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-26"><a href="#cb56-26" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-27"><a href="#cb56-27" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-28"><a href="#cb56-28" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-29"><a href="#cb56-29" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb56-30"><a href="#cb56-30" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb56-31"><a href="#cb56-31" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-32"><a href="#cb56-32" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-33"><a href="#cb56-33" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-34"><a href="#cb56-34" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-35"><a href="#cb56-35" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-36"><a href="#cb56-36" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-37"><a href="#cb56-37" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
-<span id="cb56-38"><a href="#cb56-38" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-39"><a href="#cb56-39" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-40"><a href="#cb56-40" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-41"><a href="#cb56-41" aria-hidden="true" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb56-2"><a href="#cb56-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb56-3"><a href="#cb56-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb56-4"><a href="#cb56-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb56-5"><a href="#cb56-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-6"><a href="#cb56-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb56-7"><a href="#cb56-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb56-8"><a href="#cb56-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb56-9"><a href="#cb56-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-10"><a href="#cb56-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-11"><a href="#cb56-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-12"><a href="#cb56-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-13"><a href="#cb56-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-14"><a href="#cb56-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb56-15"><a href="#cb56-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb56-16"><a href="#cb56-16" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
+<span id="cb56-17"><a href="#cb56-17" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
+<span id="cb56-18"><a href="#cb56-18" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
+<span id="cb56-19"><a href="#cb56-19" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb56-20"><a href="#cb56-20" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-21"><a href="#cb56-21" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-22"><a href="#cb56-22" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-23"><a href="#cb56-23" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
+<span id="cb56-24"><a href="#cb56-24" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
+<span id="cb56-25"><a href="#cb56-25" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-26"><a href="#cb56-26" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-27"><a href="#cb56-27" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-28"><a href="#cb56-28" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-29"><a href="#cb56-29" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb56-30"><a href="#cb56-30" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb56-31"><a href="#cb56-31" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-32"><a href="#cb56-32" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-33"><a href="#cb56-33" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-34"><a href="#cb56-34" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-35"><a href="#cb56-35" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-36"><a href="#cb56-36" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-37"><a href="#cb56-37" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
+<span id="cb56-38"><a href="#cb56-38" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-39"><a href="#cb56-39" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-40"><a href="#cb56-40" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-41"><a href="#cb56-41" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -1330,14 +1323,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb57">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
-<span id="cb57-2"><a href="#cb57-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
-<span id="cb57-3"><a href="#cb57-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
+<span id="cb57-2"><a href="#cb57-2" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
+<span id="cb57-3"><a href="#cb57-3" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 </div>
 </div>
@@ -1356,7 +1349,7 @@ <h3 class="callout-title">Organizing Directories and Files<a class="anchor" aria
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
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@@ -1395,12 +1388,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
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 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
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 <div class="codewrapper sourceCode" id="cb64">
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" aria-hidden="true" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
 </div>
 <p>Jamie needs to move her files <code>fructose.dat</code> and
 <code>sucrose.dat</code> to the <code>analyzed</code> directory. The
@@ -1442,39 +1435,39 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb66">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb66-2"><a href="#cb66-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
-<span id="cb66-3"><a href="#cb66-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
-<span id="cb66-4"><a href="#cb66-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb66-2"><a href="#cb66-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
+<span id="cb66-3"><a href="#cb66-3" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
+<span id="cb66-4"><a href="#cb66-4" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb67">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb67-2"><a href="#cb67-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb67-3"><a href="#cb67-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb67-4"><a href="#cb67-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd data</span>
-<span id="cb67-5"><a href="#cb67-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb67-2"><a href="#cb67-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb67-3"><a href="#cb67-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb67-4"><a href="#cb67-4" tabindex="-1"></a><span class="ex">$</span> cd data</span>
+<span id="cb67-5"><a href="#cb67-5" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
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 <div class="codewrapper sourceCode" id="cb68">
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
-<span id="cb68-2"><a href="#cb68-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
+<span id="cb68-2"><a href="#cb68-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
-<span id="cb69-2"><a href="#cb69-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
+<span id="cb69-2"><a href="#cb69-2" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
 </div>
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb70-2"><a href="#cb70-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb70-3"><a href="#cb70-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb70-4"><a href="#cb70-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb70-2"><a href="#cb70-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb70-3"><a href="#cb70-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb70-4"><a href="#cb70-4" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 </div>
 </div>
@@ -1484,7 +1477,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Show me the solution</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <p>The first two sets of commands achieve this objective. The first set
 uses relative paths to create the top-level directory before the
@@ -1599,7 +1592,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/03-create.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/04-pipefilter.html b/instructor/04-pipefilter.html
index 7da54de22..7466028ff 100644
--- a/instructor/04-pipefilter.html
+++ b/instructor/04-pipefilter.html
@@ -324,7 +324,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
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@@ -353,7 +353,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
 </div>
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 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -373,7 +373,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
 </div>
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 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -389,20 +389,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>The <code>-m</code> and <code>-w</code> options can also be used with
 the <code>wc</code> command to show only the number of characters or the
 number of words, respectively.</p>
-<div id="why-isnt-it-doing-anything" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="why-isnt-it-doing-anything" class="callout-inner">
-<h3 class="callout-title">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="why-isnt-it-doing-anything">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a></h3>
 <div class="callout-content">
 <p>What happens if a command is supposed to process a file, but we don’t
 give it a filename? For example, what if we type:</p>
 <div class="codewrapper sourceCode" id="cb9">
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
 </div>
 <p>but don’t type <code>*.pdb</code> (or anything else) after the
 command? Since it doesn’t have any filenames, <code>wc</code> assumes it
@@ -425,7 +424,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>The greater than symbol, <code>&gt;</code>, tells the shell to
 <strong>redirect</strong> the command’s output to a file instead of
@@ -439,7 +438,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
 </div>
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@@ -454,7 +453,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
 </div>
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 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -467,13 +466,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   15  propane.pdb
  107  total</code></pre>
 </div>
-<div id="output-page-by-page" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="output-page-by-page" class="callout-inner">
-<h3 class="callout-title">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="output-page-by-page">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a></h3>
 <div class="callout-content">
 <p>We’ll continue to use <code>cat</code> in this lesson, for
 convenience and consistency, but it has the disadvantage that it always
@@ -535,7 +533,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>The <code>-n</code> option specifies a numerical rather than an
 alphanumerical sort.</p>
@@ -549,7 +547,7 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -572,8 +570,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
-<span id="cb20-2"><a href="#cb20-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
+<span id="cb20-2"><a href="#cb20-2" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -585,20 +583,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 20, and so on. Since <code>sorted-lengths.txt</code> contains the
 lengths of our files ordered from least to greatest, the output of
 <code>head</code> must be the file with the fewest lines.</p>
-<div id="redirecting-to-the-same-file" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="redirecting-to-the-same-file" class="callout-inner">
-<h3 class="callout-title">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="redirecting-to-the-same-file">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a></h3>
 <div class="callout-content">
 <p>It’s a very bad idea to try redirecting the output of a command that
 operates on a file to the same file. For example:</p>
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>Doing something like this may give you incorrect results and/or
 delete the contents of <code>lengths.txt</code>.</p>
@@ -621,7 +618,7 @@ <h3 class="callout-title">What Does<code>&gt;&gt;</code>Mean?<a class="anchor" a
 <div class="codewrapper sourceCode" id="cb23">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -633,13 +630,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
 </div>
 <p>and:</p>
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
 </div>
 <p>Hint: Try executing each command twice in a row and then examining
 the output files.</p>
@@ -651,7 +648,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>In the first example with <code>&gt;</code>, the string ‘hello’ is
 written to <code>testfile01.txt</code>, but the file gets overwritten
@@ -682,8 +679,8 @@ <h3 class="callout-title">Appending Data<a class="anchor" aria-label="anchor" hr
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
-<span id="cb27-2"><a href="#cb27-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
+<span id="cb27-2"><a href="#cb27-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>The first three lines of <code>animals.csv</code>
 </li>
@@ -702,7 +699,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Option 3 is correct. For option 1 to be correct we would only run the
 <code>head</code> command. For option 2 to be correct we would only run
@@ -727,7 +724,7 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -751,7 +748,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -769,7 +766,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -804,7 +801,7 @@ <h3 class="callout-title">Piping Commands Together<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Option 4 is the solution. The pipe character <code>|</code> is used
 to connect the output from one command to the input of another.
@@ -857,7 +854,7 @@ <h3 class="callout-title">Pipe Reading Comprehension<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
 </div>
 <p>Hint: build the pipeline up one command at a time to test your
 understanding</p>
@@ -869,7 +866,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>The <code>head</code> command extracts the first 5 lines from
 <code>animals.csv</code>. Then, the last 3 lines are extracted from the
@@ -899,7 +896,7 @@ <h3 class="callout-title">Pipe Construction<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
 </div>
 <p>The <code>cut</code> command is used to remove or ‘cut out’ certain
 sections of each line in the file, and <code>cut</code> expects the
@@ -933,12 +930,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -982,7 +979,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
 <div class="accordion-body">
 <p>Option 4. is the correct answer. If you have difficulty understanding
 why, try running the commands, or sub-sections of the pipelines (make
@@ -1002,8 +999,8 @@ <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <p>The output is 18 lines that look like this:</p>
 <div class="codewrapper">
@@ -1021,7 +1018,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1040,7 +1037,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1058,7 +1055,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1097,7 +1094,7 @@ <h3 class="callout-title">Removing Unneeded Files<a class="anchor" aria-label="a
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>This would remove <code>.txt</code> files with one-character
 names</p></li>
@@ -1204,7 +1201,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/04-pipefilter.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/05-loop.html b/instructor/05-loop.html
index 3f739aaf0..5922520cd 100644
--- a/instructor/05-loop.html
+++ b/instructor/05-loop.html
@@ -329,7 +329,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
 </div>
 <p>We would like to print out the classification for each species, which
 is given on the second line of each file. For each file, we would need
@@ -340,24 +340,24 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
-<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
-<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span> </span>
-<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
-<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
-<span id="cb2-7"><a href="#cb2-7" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
-<span id="cb2-8"><a href="#cb2-8" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
+<span id="cb2-2"><a href="#cb2-2" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
+<span id="cb2-3"><a href="#cb2-3" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
+<span id="cb2-4"><a href="#cb2-4" tabindex="-1"></a><span class="cf">do</span> </span>
+<span id="cb2-5"><a href="#cb2-5" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
+<span id="cb2-6"><a href="#cb2-6" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
+<span id="cb2-7"><a href="#cb2-7" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
+<span id="cb2-8"><a href="#cb2-8" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
 </div>
 <p>and we can apply this to our example like this:</p>
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb3-3"><a href="#cb3-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb3-4"><a href="#cb3-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb3-5"><a href="#cb3-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -369,13 +369,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 unicorn.dat
 CLASSIFICATION: equus monoceros</code></pre>
 </div>
-<div id="follow-the-prompt" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="follow-the-prompt" class="callout-inner">
-<h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="follow-the-prompt">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a></h3>
 <div class="callout-content">
 <p>The shell prompt changes from <code>$</code> to <code>&gt;</code> and
 back again as we were typing in our loop. The second prompt,
@@ -415,13 +414,12 @@ <h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor"
 runs the <code>head</code> command on that file, and <code>tail</code>
 on the output of that. Since the list was only three items, the shell
 exits the <code>for</code> loop.</p>
-<div id="same-symbols-different-meanings" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="same-symbols-different-meanings" class="callout-inner">
-<h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="same-symbols-different-meanings">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a></h3>
 <div class="callout-content">
 <p>Here we see <code>&gt;</code> being used as a shell prompt, whereas
 <code>&gt;</code> is also used to redirect output. Similarly,
@@ -446,19 +444,19 @@ <h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb5-2"><a href="#cb5-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb5-3"><a href="#cb5-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb5-4"><a href="#cb5-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>or:</p>
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb6-4"><a href="#cb6-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb6-2"><a href="#cb6-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb6-3"><a href="#cb6-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb6-4"><a href="#cb6-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>it would work exactly the same way. <em>Don’t do this.</em> Programs
 are only useful if people can understand them, so meaningless names
@@ -489,15 +487,15 @@ <h3 class="callout-title">Write your own loop<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
-<span id="cb7-2"><a href="#cb7-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb7-3"><a href="#cb7-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
-<span id="cb7-4"><a href="#cb7-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
+<span id="cb7-2"><a href="#cb7-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb7-3"><a href="#cb7-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
+<span id="cb7-4"><a href="#cb7-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -537,19 +535,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
-<span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb10-2"><a href="#cb10-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb10-3"><a href="#cb10-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
+<span id="cb10-4"><a href="#cb10-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Now, what is the output of the following code?</p>
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
-<span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Why do these two loops give different outputs?</p>
 </div>
@@ -560,7 +558,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The first code block gives the same output on each iteration through
 the loop. Bash expands the wildcard <code>*.pdb</code> within the loop
@@ -570,10 +568,10 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb12-3"><a href="#cb12-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-4"><a href="#cb12-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb12-3"><a href="#cb12-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-4"><a href="#cb12-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -615,10 +613,10 @@ <h3 class="callout-title">Limiting Sets of Files<a class="anchor" aria-label="an
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
-<span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb15-3"><a href="#cb15-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb15-4"><a href="#cb15-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
+<span id="cb15-2"><a href="#cb15-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb15-3"><a href="#cb15-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb15-4"><a href="#cb15-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>No files are listed.</li>
 <li>All files are listed.</li>
@@ -633,7 +631,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so any file name starting with the letter c, followed by
@@ -654,10 +652,10 @@ <h3 class="callout-title">Limiting Sets of Files<em>(continued)</em><a class="an
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
-<span id="cb16-2"><a href="#cb16-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb16-3"><a href="#cb16-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb16-4"><a href="#cb16-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
+<span id="cb16-2"><a href="#cb16-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb16-3"><a href="#cb16-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb16-4"><a href="#cb16-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>The same files would be listed.</li>
 <li>All the files are listed this time.</li>
@@ -673,7 +671,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so a file name with zero or more characters before a letter
@@ -695,11 +693,11 @@ <h3 class="callout-title">Saving to a File in a Loop - Part One<a class="anchor"
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb17-2"><a href="#cb17-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb17-3"><a href="#cb17-3" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
-<span id="cb17-4"><a href="#cb17-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
-<span id="cb17-5"><a href="#cb17-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb17-2"><a href="#cb17-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb17-3"><a href="#cb17-3" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
+<span id="cb17-4"><a href="#cb17-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
+<span id="cb17-5"><a href="#cb17-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>Prints <code>cubane.pdb</code>, <code>ethane.pdb</code>,
 <code>methane.pdb</code>, <code>octane.pdb</code>,
@@ -722,7 +720,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li>The text from each file in turn gets written to the
 <code>alkanes.pdb</code> file. However, the file gets overwritten on
@@ -745,10 +743,10 @@ <h3 class="callout-title">Saving to a File in a Loop - Part Two<a class="anchor"
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb18-4"><a href="#cb18-4" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb18-4"><a href="#cb18-4" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal"><li>All of the text from <code>cubane.pdb</code>,
 <code>ethane.pdb</code>, <code>methane.pdb</code>,
@@ -774,7 +772,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>3 is the correct answer. <code>&gt;&gt;</code> appends to a file,
 rather than overwriting it with the redirected output from a command.
@@ -790,11 +788,11 @@ <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb19-2"><a href="#cb19-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb19-3"><a href="#cb19-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb19-4"><a href="#cb19-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb19-5"><a href="#cb19-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb19-2"><a href="#cb19-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb19-3"><a href="#cb19-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb19-4"><a href="#cb19-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb19-5"><a href="#cb19-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>The shell starts by expanding <code>*.dat</code> to create the list
 of files it will process. The <strong>loop body</strong> then executes
@@ -804,7 +802,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
 </div>
 <p>prints:</p>
 <div class="codewrapper">
@@ -818,11 +816,11 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb22-2"><a href="#cb22-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb22-3"><a href="#cb22-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
-<span id="cb22-4"><a href="#cb22-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb22-5"><a href="#cb22-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb22-2"><a href="#cb22-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb22-3"><a href="#cb22-3" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
+<span id="cb22-4"><a href="#cb22-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb22-5"><a href="#cb22-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>because then the first time through the loop, when
 <code>$filename</code> expanded to <code>basilisk.dat</code>, the shell
@@ -830,13 +828,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <code>head</code> and <code>tail</code> combination selects lines 81-100
 from whatever file is being processed (assuming the file has at least
 100 lines).</p>
-<div id="spaces-in-names" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="spaces-in-names" class="callout-inner">
-<h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="spaces-in-names">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a></h3>
 <div class="callout-content">
 <p>Spaces are used to separate the elements of the list that we are
 going to loop over. If one of those elements contains a space character,
@@ -849,10 +846,10 @@ <h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
-<span id="cb24-2"><a href="#cb24-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb24-3"><a href="#cb24-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb24-4"><a href="#cb24-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
+<span id="cb24-2"><a href="#cb24-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb24-3"><a href="#cb24-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb24-4"><a href="#cb24-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>It is simpler to avoid using spaces (or other special characters) in
 filenames.</p>
@@ -892,13 +889,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>because that would expand to:</p>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>This wouldn’t back up our files, instead we get an error:</p>
 <div class="codewrapper">
@@ -915,10 +912,10 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb30-2"><a href="#cb30-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb30-3"><a href="#cb30-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
-<span id="cb30-4"><a href="#cb30-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb30-2"><a href="#cb30-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb30-3"><a href="#cb30-3" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
+<span id="cb30-4"><a href="#cb30-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>This loop runs the <code>cp</code> command once for each filename.
 The first time, when <code>$filename</code> expands to
@@ -926,19 +923,19 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
 </div>
 <p>The second time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
 </div>
 <p>The third and last time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
 </div>
 <p>Since the <code>cp</code> command does not normally produce any
 output, it’s hard to check that the loop is working correctly. However,
@@ -965,12 +962,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -989,10 +986,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb36-3"><a href="#cb36-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb36-4"><a href="#cb36-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb36-3"><a href="#cb36-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb36-4"><a href="#cb36-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1015,14 +1012,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>Using the <kbd>←</kbd>, Nelle navigates to the <code>echo</code>
 command and changes it to <code>bash goostats.sh</code>:</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>When she presses <kbd>Enter</kbd>, the shell runs the modified
 command. However, nothing appears to happen — there is no output. After
@@ -1034,16 +1031,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
-<div id="beginning-and-end" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="beginning-and-end" class="callout-inner">
-<h3 class="callout-title">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="beginning-and-end">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a></h3>
 <div class="callout-content">
 <p>We can move to the beginning of a line in the shell by typing
 <kbd>Ctrl</kbd>+<kbd>A</kbd> and to the end using
@@ -1067,14 +1063,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <code>cat stats-NENE01729B.txt</code> to examine one of the output
 files. It looks good, so she decides to get some coffee and catch up on
 her reading.</p>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout-inner">
-<h3 class="callout-title">Those Who Know History Can Choose to Repeat
-It<a class="anchor" aria-label="anchor" href="#those-who-know-history-can-choose-to-repeat-it"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="those-who-know-history-can-choose-to-repeat-it">Those Who Know History Can Choose to Repeat
+It<a class="anchor" aria-label="anchor" href="#those-who-know-history-can-choose-to-repeat-it"></a></h3>
 <div class="callout-content">
 <p>Another way to repeat previous work is to use the
 <code>history</code> command to get a list of the last few hundred
@@ -1084,7 +1079,7 @@ <h3 class="callout-title">Those Who Know History Can Choose to Repeat
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1101,13 +1096,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 </div>
 </div>
-<div id="other-history-commands" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-history-commands" class="callout-inner">
-<h3 class="callout-title">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-history-commands">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a></h3>
 <div class="callout-content">
 <p>There are a number of other shortcut commands for getting at the
 history.</p>
@@ -1148,30 +1142,30 @@ <h3 class="callout-title">Doing a Dry Run<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb44-2"><a href="#cb44-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb44-3"><a href="#cb44-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb44-4"><a href="#cb44-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb44-2"><a href="#cb44-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb44-3"><a href="#cb44-3" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb44-4"><a href="#cb44-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>What is the difference between the two loops below, and which one
 would we want to run?</p>
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 1</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Version 1</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 2</span></span>
-<span id="cb46-2"><a href="#cb46-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb46-3"><a href="#cb46-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb46-4"><a href="#cb46-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
-<span id="cb46-5"><a href="#cb46-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="co"># Version 2</span></span>
+<span id="cb46-2"><a href="#cb46-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb46-3"><a href="#cb46-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb46-4"><a href="#cb46-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
+<span id="cb46-5"><a href="#cb46-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -1181,7 +1175,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The second version is the one we want to run. This prints to screen
 everything enclosed in the quote marks, expanding the loop variable name
@@ -1214,13 +1208,13 @@ <h3 class="callout-title">Nested Loops<a class="anchor" aria-label="anchor" href
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
-<span id="cb47-2"><a href="#cb47-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb47-3"><a href="#cb47-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
-<span id="cb47-4"><a href="#cb47-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
-<span id="cb47-5"><a href="#cb47-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
-<span id="cb47-6"><a href="#cb47-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
-<span id="cb47-7"><a href="#cb47-7" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
+<span id="cb47-2"><a href="#cb47-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb47-3"><a href="#cb47-3" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
+<span id="cb47-4"><a href="#cb47-4" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
+<span id="cb47-5"><a href="#cb47-5" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
+<span id="cb47-6"><a href="#cb47-6" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
+<span id="cb47-7"><a href="#cb47-7" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -1230,7 +1224,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <p>We have a nested loop, i.e. contained within another loop, so for
 each species in the outer loop, the inner loop (the nested loop)
@@ -1328,7 +1322,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/05-loop.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/06-script.html b/instructor/06-script.html
index 1d8282fa4..e66122cc2 100644
--- a/instructor/06-script.html
+++ b/instructor/06-script.html
@@ -328,8 +328,8 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>The command <code>nano middle.sh</code> opens the file
 <code>middle.sh</code> within the text editor ‘nano’ (which runs within
@@ -351,7 +351,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -364,13 +364,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Sure enough, our script’s output is exactly what we would get if we
 ran that pipeline directly.</p>
-<div id="text-vs.-whatever" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="text-vs.-whatever" class="callout-inner">
-<h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs.-whatever"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="text-vs--whatever">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs--whatever"></a></h3>
 <div class="callout-content">
 <p>We usually call programs like Microsoft Word or LibreOffice Writer
 “text editors”, but we need to be a bit more careful when it comes to
@@ -393,7 +392,7 @@ <h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>Now, within “nano”, replace the text <code>octane.pdb</code> with the
 special variable called <code>$1</code>:</p>
@@ -404,7 +403,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -419,7 +418,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -430,13 +429,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 ATOM     12  H           1      -0.048  -1.362  -0.205  1.00  0.00
 ATOM     13  H           1      -1.183   0.500  -1.412  1.00  0.00</code></pre>
 </div>
-<div id="double-quotes-around-arguments" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="double-quotes-around-arguments" class="callout-inner">
-<h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="double-quotes-around-arguments">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a></h3>
 <div class="callout-content">
 <p>For the same reason that we put the loop variable inside
 double-quotes, in case the filename happens to contain any spaces, we
@@ -457,14 +455,14 @@ <h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code>head -n "$2" "$1" | tail -n "$3"</code></pre>
 <p>We can now run:</p>
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -480,7 +478,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -498,7 +496,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code># Select lines from the middle of a file.
 # Usage: bash middle.sh filename end_line num_lines
@@ -515,7 +513,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <p>because <code>wc -l</code> lists the number of lines in the files
 (recall that <code>wc</code> stands for ‘word count’, adding the
@@ -535,7 +533,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
 </div>
 <pre class="source"><code># Sort files by their length.
 # Usage: bash sorted.sh one_or_more_filenames
@@ -543,7 +541,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -596,21 +594,21 @@ <h3 class="callout-title">List Unique Species<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
-<span id="cb25-2"><a href="#cb25-2" aria-hidden="true" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
-<span id="cb25-3"><a href="#cb25-3" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb25-4"><a href="#cb25-4" aria-hidden="true" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
-<span id="cb25-5"><a href="#cb25-5" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
-<span id="cb25-6"><a href="#cb25-6" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb25-7"><a href="#cb25-7" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
-<span id="cb25-8"><a href="#cb25-8" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
-<span id="cb25-9"><a href="#cb25-9" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
-<span id="cb25-10"><a href="#cb25-10" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
+<span id="cb25-2"><a href="#cb25-2" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
+<span id="cb25-3"><a href="#cb25-3" tabindex="-1"></a></span>
+<span id="cb25-4"><a href="#cb25-4" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
+<span id="cb25-5"><a href="#cb25-5" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
+<span id="cb25-6"><a href="#cb25-6" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb25-7"><a href="#cb25-7" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
+<span id="cb25-8"><a href="#cb25-8" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
+<span id="cb25-9"><a href="#cb25-9" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
+<span id="cb25-10"><a href="#cb25-10" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -624,7 +622,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
 </div>
 <p>The file <code>redo-figure-3.sh</code> now contains:</p>
 <pre class="source"><code>297 bash goostats.sh NENE01729B.txt stats-NENE01729B.txt
@@ -649,7 +647,7 @@ <h3 class="callout-title">Why Record Commands in the History Before
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
 </div>
 <p>the last command in the file is the <code>history</code> command
 itself, i.e., the shell has added <code>history</code> to the command
@@ -664,7 +662,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>If a command causes something to crash or hang, it might be useful to
 know what that command was, in order to investigate the problem. Were
@@ -689,37 +687,37 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
 </div>
 <p>She creates a file using <code>nano</code> …</p>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
 </div>
 <p>…which contains the following:</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb31-3"><a href="#cb31-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb31-4"><a href="#cb31-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb31-5"><a href="#cb31-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb31-6"><a href="#cb31-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb31-3"><a href="#cb31-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb31-4"><a href="#cb31-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb31-5"><a href="#cb31-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb31-6"><a href="#cb31-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>She saves this in a file called <code>do-stats.sh</code> so that she
 can now re-do the first stage of her analysis by typing:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>She can also do this:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
 </div>
 <p>so that the output is just the number of files processed rather than
 the names of the files that were processed.</p>
@@ -729,12 +727,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>The advantage is that this always selects the right files: she
 doesn’t have to remember to exclude the ‘Z’ files. The disadvantage is
@@ -759,15 +757,15 @@ <h3 class="callout-title">Variables in Shell Scripts<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
-<span id="cb35-2"><a href="#cb35-2" aria-hidden="true" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
+<span id="cb35-2"><a href="#cb35-2" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
 </div>
 <p>While you are in the <code>alkanes</code> directory, you type the
 following command:</p>
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
 </div>
 <p>Which of the following outputs would you expect to see?</p>
 <ol style="list-style-type: decimal"><li>All of the lines between the first and the last lines of each file
@@ -786,7 +784,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The correct answer is 2.</p>
 <p>The special variables <code>$1</code>, <code>$2</code> and
@@ -795,8 +793,8 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
-<span id="cb37-2"><a href="#cb37-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
+<span id="cb37-2"><a href="#cb37-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
 </div>
 <p>The shell does not expand <code>'*.pdb'</code> because it is enclosed
 by quote marks. As such, the first argument to the script is
@@ -822,7 +820,7 @@ <h3 class="callout-title">Find the Longest File With a Given
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
 </div>
 <p>would print the name of the <code>.pdb</code> file in
 <code>shell-lesson-data/exercise-data/alkanes</code> that has the most
@@ -831,7 +829,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -841,18 +839,18 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
-<span id="cb40-3"><a href="#cb40-3" aria-hidden="true" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
-<span id="cb40-4"><a href="#cb40-4" aria-hidden="true" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
-<span id="cb40-5"><a href="#cb40-5" aria-hidden="true" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
-<span id="cb40-6"><a href="#cb40-6" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb40-7"><a href="#cb40-7" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
+<span id="cb40-3"><a href="#cb40-3" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
+<span id="cb40-4"><a href="#cb40-4" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
+<span id="cb40-5"><a href="#cb40-5" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
+<span id="cb40-6"><a href="#cb40-6" tabindex="-1"></a></span>
+<span id="cb40-7"><a href="#cb40-7" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <p>The first part of the pipeline, <code>wc -l $1/*.$2 | sort -n</code>,
 counts the lines in each file and sorts them numerically (largest last).
@@ -885,23 +883,23 @@ <h3 class="callout-title">Script Reading Comprehension<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 1</span></span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="co"># Script 1</span></span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 2</span></span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
-<span id="cb42-3"><a href="#cb42-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb42-4"><a href="#cb42-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
-<span id="cb42-5"><a href="#cb42-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="co"># Script 2</span></span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
+<span id="cb42-3"><a href="#cb42-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb42-4"><a href="#cb42-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
+<span id="cb42-5"><a href="#cb42-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 3</span></span>
-<span id="cb43-2"><a href="#cb43-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="co"># Script 3</span></span>
+<span id="cb43-2"><a href="#cb43-2" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
 </div>
 </div>
 </div>
@@ -911,7 +909,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solutions</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>In each case, the shell expands the wildcard in <code>*.pdb</code>
 before passing the resulting list of file names as arguments to the
@@ -949,26 +947,26 @@ <h3 class="callout-title">Debugging Scripts<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb45-6"><a href="#cb45-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb45-6"><a href="#cb45-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>When you run it from the <code>north-pacific-gyre</code>
 directory:</p>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>the output is blank. To figure out why, re-run the script using the
 <code>-x</code> option:</p>
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>What is the output showing you? Which line is responsible for the
 error?</p>
@@ -980,7 +978,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>The <code>-x</code> option causes <code>bash</code> to run in debug
 mode. This prints out each command as it is run, which will help you to
@@ -1076,7 +1074,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/06-script.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/07-find.html b/instructor/07-find.html
index 5d4bfd5ee..c8ce0e953 100644
--- a/instructor/07-find.html
+++ b/instructor/07-find.html
@@ -321,9 +321,9 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
-<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
+<span id="cb1-3"><a href="#cb1-3" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -344,7 +344,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -367,7 +367,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -386,7 +386,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -400,7 +400,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -417,7 +417,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -435,7 +435,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -448,7 +448,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -463,7 +463,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -486,7 +486,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -501,7 +501,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -552,7 +552,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The correct answer is 3, because the <code>-w</code> option looks
 only for whole-word matches. The other options will also match ‘of’ when
@@ -561,13 +561,12 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="wildcards" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a></h3>
 <div class="callout-content">
 <p><code>grep</code>‘s real power doesn’t come from its options, though;
 it comes from the fact that patterns can include wildcards. (The
@@ -580,7 +579,7 @@ <h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -631,13 +630,13 @@ <h3 class="callout-title">Tracking a Species<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span></span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-6"><a href="#cb28-6" aria-hidden="true" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
-<span id="cb28-7"><a href="#cb28-7" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a><span class="op">&gt;</span></span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-6"><a href="#cb28-6" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
+<span id="cb28-7"><a href="#cb28-7" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
 </div>
 <p>Hint: use <code>man grep</code> to look for how to grep text
 recursively in a directory and <code>man cut</code> to select more than
@@ -652,7 +651,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <pre class="source"><code>grep -w $1 -r $2 | cut -d : -f 2 | cut -d , -f 1,3 &gt; $1.txt</code></pre>
 <p>Actually, you can swap the order of the two cut commands and it still
@@ -663,7 +662,7 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
 </div>
 </div>
 </div>
@@ -700,7 +699,7 @@ <h3 class="callout-title">Little Women<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solutions</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <pre class="source"><code>for sis in Jo Meg Beth Amy
 do
@@ -763,7 +762,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -799,7 +798,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -816,7 +815,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -839,7 +838,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -854,7 +853,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
 </div>
 <p><code>find</code> did what we asked; we just asked for the wrong
 thing.</p>
@@ -866,7 +865,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -875,13 +874,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <span><span class="va">.</span><span class="op">/</span><span class="va">writing</span><span class="op">/</span><span class="va">haiku.txt</span></span>
 <span><span class="va">.</span><span class="op">/</span><span class="va">numbers.txt</span></span></code></pre>
 </div>
-<div id="listing-vs.-finding" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="listing-vs.-finding" class="callout-inner">
-<h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs.-finding"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="listing-vs--finding">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs--finding"></a></h3>
 <div class="callout-content">
 <p><code>ls</code> and <code>find</code> can be made to do similar
 things given the right options, but under normal circumstances,
@@ -900,7 +898,7 @@ <h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -920,7 +918,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
 </div>
 <p>which is what we wanted. This expansion is exactly what the shell
 does when it expands wildcards like <code>*</code> and <code>?</code>,
@@ -934,7 +932,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -968,7 +966,7 @@ <h3 class="callout-title">Matching and Subtracting<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>Option 1 is correct. Putting the match expression in quotes prevents
 the shell expanding it, so it gets passed to the <code>find</code>
@@ -984,13 +982,12 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="binary-files" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="binary-files" class="callout-inner">
-<h3 class="callout-title">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="binary-files">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a></h3>
 <div class="callout-content">
 <p>We have focused exclusively on finding patterns in text files. What
 if your data is stored as images, in databases, or in some other
@@ -1035,7 +1032,7 @@ <h3 class="callout-title">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -1045,7 +1042,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p>Find all files with a <code>.dat</code> extension recursively
 from the current directory</p></li>
@@ -1142,7 +1139,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/07-find.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/404.html b/instructor/404.html
index d08731cba..6d49de785 100644
--- a/instructor/404.html
+++ b/instructor/404.html
@@ -319,8 +319,8 @@ <h1>Page not found</h1>
   "url": "https://swcarpentry.github.io/shell-novice/instructor/404.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/404.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/CODE_OF_CONDUCT.html b/instructor/CODE_OF_CONDUCT.html
index 6ba5e0f01..b4fa87262 100644
--- a/instructor/CODE_OF_CONDUCT.html
+++ b/instructor/CODE_OF_CONDUCT.html
@@ -339,7 +339,7 @@ <h1>Contributor Code of Conduct</h1>
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/CODE_OF_CONDUCT.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/LICENSE.html b/instructor/LICENSE.html
index a359010ba..cd5e28200 100644
--- a/instructor/LICENSE.html
+++ b/instructor/LICENSE.html
@@ -391,7 +391,7 @@ <h1>Licenses</h1>
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/LICENSE.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/aio.html b/instructor/aio.html
index da48cc236..361c8e293 100644
--- a/instructor/aio.html
+++ b/instructor/aio.html
@@ -408,7 +408,7 @@ <h3 id="the-shell">The Shell<a class="anchor" aria-label="anchor" href="#the-she
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span></span></code></pre>
 </div>
 <p>The shell typically uses <code>$</code> as the prompt, but may use a
 different symbol. In the examples for this lesson, we’ll show the prompt
@@ -428,7 +428,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="ex">nelle@localhost</span> $</span></code></pre>
 </div>
 <p>The prompt might even include more than this. Do not worry if your
 prompt is not just a short <code>$</code>. This lesson does not depend
@@ -441,7 +441,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -449,12 +449,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="output" tabindex="0"><code>Desktop     Downloads   Movies      Pictures
 Documents   Library     Music       Public</code></pre>
 </div>
-<div id="command-not-found" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="command-not-found" class="callout-inner">
-<h3 class="callout-title">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="command-not-found">Command not found<a class="anchor" aria-label="anchor" href="#command-not-found"></a>
 </h3>
 <div class="callout-content">
 <p>If the shell can’t find a program whose name is the command you
@@ -462,7 +462,7 @@ <h3 class="callout-title">Command not found<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ks</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -585,7 +585,7 @@ <h3 class="card-title">Objectives</h3>
   <h3 class="accordion-header" id="headingInstructor1">
 <div class="note-square"><i aria-hidden="true" class="callout-icon" data-feather="edit-2"></i></div>Instructor Note</h3>
 </button>
-<div id="collapseInstructor1" class="accordion-collapse collapse" data-bs-parent="#accordionInstructor1" aria-labelledby="headingInstructor1">
+<div id="collapseInstructor1" class="accordion-collapse collapse" aria-labelledby="headingInstructor1" data-bs-parent="#accordionInstructor1">
 <div class="accordion-body">
 <p>Introducing and navigating the filesystem in the shell (covered in <a href="02-filedir.html">Navigating Files and Directories</a> section) can
 be confusing. You may have both terminal and GUI file explorer open side
@@ -613,7 +613,7 @@ <h3 class="accordion-header" id="headingInstructor1">
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -622,12 +622,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Here, the computer’s response is <code>/Users/nelle</code>, which is
 Nelle’s <strong>home directory</strong>:</p>
-<div id="home-directory-variation" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="home-directory-variation" class="callout-inner">
-<h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="home-directory-variation">Home Directory Variation<a class="anchor" aria-label="anchor" href="#home-directory-variation"></a>
 </h3>
 <div class="callout-content">
 <p>The home directory path will look different on different operating
@@ -667,12 +667,12 @@ <h3 class="callout-title">Home Directory Variation<a class="anchor" aria-label="
 first part of its name. Similarly, we know that <code>/Users</code> is
 stored inside the root directory <code>/</code> because its name begins
 with <code>/</code>.</p>
-<div id="slashes" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="slashes" class="callout-inner">
-<h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="slashes">Slashes<a class="anchor" aria-label="anchor" href="#slashes"></a>
 </h3>
 <div class="callout-content">
 <p>Notice that there are two meanings for the <code>/</code> character.
@@ -698,7 +698,7 @@ <h3 class="callout-title">Slashes<a class="anchor" aria-label="anchor" href="#sl
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -725,7 +725,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -737,12 +737,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <strong>sub-directories</strong>. Any names in the output that don’t
 have a classification symbol are <strong>files</strong> in the current
 working directory.</p>
-<div id="clearing-your-terminal" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="clearing-your-terminal" class="callout-inner">
-<h3 class="callout-title">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="clearing-your-terminal">Clearing your terminal<a class="anchor" aria-label="anchor" href="#clearing-your-terminal"></a>
 </h3>
 <div class="callout-content">
 <p>If your screen gets too cluttered, you can clear your terminal using
@@ -766,7 +766,7 @@ <h3 id="getting-help">Getting help<a class="anchor" aria-label="anchor" href="#g
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <ol start="2" style="list-style-type: decimal">
 <li>We can read its manual with <code>man</code> (available on Linux and
@@ -775,15 +775,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>We’ll describe both ways next.</p>
-<div id="help-for-built-in-commands" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="help-for-built-in-commands" class="callout-inner">
-<h3 class="callout-title">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="help-for-built-in-commands">Help for built-in commands<a class="anchor" aria-label="anchor" href="#help-for-built-in-commands"></a>
 </h3>
 <div class="callout-content">
 <p>Some commands are built in to the Bash shell, rather than existing as
@@ -804,7 +804,7 @@ <h4 id="the---help-option">The <code>--help</code> option<a class="anchor" aria-
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -835,12 +835,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   -F, --classify             append indicator (one of */=&gt;@|) to entries
 ...        ...        ...</code></pre>
 </div>
-<div id="unsupported-command-line-options" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="unsupported-command-line-options" class="callout-inner">
-<h3 class="callout-title">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="unsupported-command-line-options">Unsupported command-line options<a class="anchor" aria-label="anchor" href="#unsupported-command-line-options"></a>
 </h3>
 <div class="callout-content">
 <p>If you try to use an option that is not supported, <code>ls</code>
@@ -848,7 +848,7 @@ <h3 class="callout-title">Unsupported command-line options<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-j</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -867,7 +867,7 @@ <h4 id="the-man-command">The <code>man</code> command<a class="anchor" aria-labe
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> man ls</span></code></pre>
 </div>
 <p>This command will turn your terminal into a page with a description
 of the <code>ls</code> command and its options.</p>
@@ -881,12 +881,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <kbd>Shift</kbd>+<kbd>N</kbd> (for moving backward).</p>
 <p>To <strong>quit</strong> the <code>man</code> pages, press
 <kbd>Q</kbd>.</p>
-<div id="manual-pages-on-the-web" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="manual-pages-on-the-web" class="callout-inner">
-<h3 class="callout-title">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="manual-pages-on-the-web">Manual pages on the web<a class="anchor" aria-label="anchor" href="#manual-pages-on-the-web"></a>
 </h3>
 <div class="callout-content">
 <p>Of course, there is a third way to access help for commands:
@@ -922,7 +922,7 @@ <h3 class="callout-title">Exploring More<code>ls</code>Options<a class="anchor"
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>-l</code> option makes <code>ls</code> use a
 <strong>l</strong>ong listing format, showing not only the
@@ -958,7 +958,7 @@ <h3 class="callout-title">Listing in Reverse Chronological Order<a class="anchor
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The most recently changed file is listed last when using
 <code>-rt</code>. This can be very useful for finding your most recent
@@ -983,7 +983,7 @@ <h3 id="exploring-other-directories">Exploring Other Directories<a class="anchor
 <div class="codewrapper sourceCode" id="cb14">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb14-1"><a href="#cb14-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1014,7 +1014,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> Desktop/shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1036,9 +1036,9 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a><span class="ex">$</span> cd exercise-data</span></code></pre>
 </div>
 <p>These commands will move us from our home directory into our Desktop
 directory, then into the <code>shell-lesson-data</code> directory, then
@@ -1055,7 +1055,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1065,7 +1065,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1078,7 +1078,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb23">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> cd shell-lesson-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1095,7 +1095,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> cd ..</span></code></pre>
 </div>
 <p><code>..</code> is a special directory name meaning “the directory
 containing this one”, or more succinctly, the <strong>parent</strong> of
@@ -1105,7 +1105,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1118,7 +1118,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> <span class="at">-a</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1136,12 +1136,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>Note that in most command line tools, multiple options can be
 combined with a single <code>-</code> and no spaces between the options;
 <code>ls -F -a</code> is equivalent to <code>ls -Fa</code>.</p>
-<div id="other-hidden-files" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-hidden-files" class="callout-inner">
-<h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-hidden-files">Other Hidden Files<a class="anchor" aria-label="anchor" href="#other-hidden-files"></a>
 </h3>
 <div class="callout-content">
 <p>In addition to the hidden directories <code>..</code> and
@@ -1164,14 +1164,14 @@ <h3 class="callout-title">Other Hidden Files<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> cd</span></code></pre>
 </div>
 <p>How can you check what happened? <code>pwd</code> gives us the
 answer!</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1188,7 +1188,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data</span></code></pre>
 </div>
 <p>Check that we’ve moved to the right place by running <code>pwd</code>
 and <code>ls -F</code>.</p>
@@ -1214,7 +1214,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1224,16 +1224,16 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cd /Users/nelle/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Run <code>pwd</code> and <code>ls -F</code> to ensure that we’re in
 the directory we expect.</p>
-<div id="two-more-shortcuts" class="callout callout">
+<div id="callout8" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-more-shortcuts" class="callout-inner">
-<h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-more-shortcuts">Two More Shortcuts<a class="anchor" aria-label="anchor" href="#two-more-shortcuts"></a>
 </h3>
 <div class="callout-content">
 <p>The shell interprets a tilde (<code>~</code>) character at the start
@@ -1258,20 +1258,20 @@ <h3 class="callout-title">Two More Shortcuts<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span></code></pre>
 </div>
 <p>Then <code>cd</code> into the <code>exercise-data/creatures</code>
 directory</p>
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/creatures</span></code></pre>
 </div>
 <p>Now if you run</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cd <span class="at">-</span></span></code></pre>
 </div>
 <p>you’ll see you’re back in <code>~/Desktop/shell-lesson-data</code>.
 Run <code>cd -</code> again and you’re back in
@@ -1309,7 +1309,7 @@ <h3 class="callout-title">Absolute vs Relative Paths<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>No: <code>.</code> stands for the current directory.</p></li>
@@ -1355,7 +1355,7 @@ <h3 class="callout-title">Relative Path Resolution<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>No: there <em>is</em> a directory <code>backup</code> in
@@ -1401,7 +1401,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>No: <code>pwd</code> is not the name of a directory.</p></li>
@@ -1424,7 +1424,7 @@ <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <figure><img src="../fig/shell_command_syntax.svg" alt="General syntax of a shell command" class="figure mx-auto d-block"></figure><p><code>ls</code> is the <strong>command</strong>, with an
 <strong>option</strong> <code>-F</code> and an <strong>argument</strong>
@@ -1450,8 +1450,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data</span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-s</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1466,7 +1466,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-S</span> exercise-data</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1480,7 +1480,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> /</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1489,12 +1489,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 Library/              Users/
 Network/              Volumes/</code></pre>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout callout">
+<div id="callout9" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="when-to-use-short-or-long-options" class="callout-inner">
-<h3 class="callout-title">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="when-to-use-short-or-long-options">When to use short or long options<a class="anchor" aria-label="anchor" href="#when-to-use-short-or-long-options"></a>
 </h3>
 <div class="callout-content">
 <p>When options exist as both short and long options:</p>
@@ -1528,7 +1528,7 @@ <h3 id="nelles-pipeline-organizing-files">Nelle’s Pipeline: Organizing Files<a
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>This command is a lot to type, but she can let the shell do most of
 the work through what is called <strong>tab completion</strong>. If she
@@ -1536,14 +1536,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> ls nor</span></code></pre>
 </div>
 <p>and then presses <kbd>Tab</kbd> (the tab key on her keyboard), the
 shell automatically completes the directory name for her:</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/</span></code></pre>
 </div>
 <p>Pressing <kbd>Tab</kbd> again does nothing, since there are multiple
 possibilities; pressing <kbd>Tab</kbd> twice brings up a list of all the
@@ -1554,15 +1554,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb51">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb51-1"><a href="#cb51-1" tabindex="-1"></a><span class="ex">$</span> ls north-pacific-gyre/goo</span></code></pre>
 </div>
 <p>To see all of those files, she can press <kbd>Tab</kbd> twice
 more.</p>
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
-<span id="cb52-2"><a href="#cb52-2" aria-hidden="true" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="fu">ls</span> north-pacific-gyre/goo</span>
+<span id="cb52-2"><a href="#cb52-2" tabindex="-1"></a><span class="ex">goodiff.sh</span>   goostats.sh</span></code></pre>
 </div>
 <p>This is called <strong>tab completion</strong>, and we will see it in
 many other tools as we go on.</p>
@@ -1662,7 +1662,7 @@ <h3 id="step-one-see-where-we-are-and-what-we-already-have">Step one: see where
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1674,8 +1674,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> cd exercise-data/writing/</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1691,7 +1691,7 @@ <h3 id="create-a-directory">Create a directory<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> mkdir thesis</span></code></pre>
 </div>
 <p>As you might guess from its name, <code>mkdir</code> means ‘make
 directory’. Since <code>thesis</code> is a relative path (i.e., does not
@@ -1700,7 +1700,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1712,7 +1712,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb8">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> thesis</span></code></pre>
 </div>
 <p>Note that <code>mkdir</code> is not limited to creating single
 directories one at a time. The <code>-p</code> option allows
@@ -1721,7 +1721,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> ../project/data ../project/results</span></code></pre>
 </div>
 <p>The <code>-R</code> option to the <code>ls</code> command will list
 all nested subdirectories within a directory. Let’s use
@@ -1730,7 +1730,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-FR</span> ../project</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1742,12 +1742,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 
 ../project/results:</code></pre>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="two-ways-of-doing-the-same-thing" class="callout-inner">
-<h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="two-ways-of-doing-the-same-thing">Two ways of doing the same thing<a class="anchor" aria-label="anchor" href="#two-ways-of-doing-the-same-thing"></a>
 </h3>
 <div class="callout-content">
 <p>Using the shell to create a directory is no different than using a
@@ -1759,12 +1759,12 @@ <h3 class="callout-title">Two ways of doing the same thing<a class="anchor" aria
 </div>
 </div>
 </div>
-<div id="good-names-for-files-and-directories" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="good-names-for-files-and-directories" class="callout-inner">
-<h3 class="callout-title">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="good-names-for-files-and-directories">Good names for files and directories<a class="anchor" aria-label="anchor" href="#good-names-for-files-and-directories"></a>
 </h3>
 <div class="callout-content">
 <p>Complicated names of files and directories can make your life painful
@@ -1804,7 +1804,7 @@ <h3 class="callout-title">Good names for files and directories<a class="anchor"
   <h3 class="accordion-header" id="headingInstructor1">
 <div class="note-square"><i aria-hidden="true" class="callout-icon" data-feather="edit-2"></i></div>Instructor Note</h3>
 </button>
-<div id="collapseInstructor1" class="accordion-collapse collapse" data-bs-parent="#accordionInstructor1" aria-labelledby="headingInstructor1">
+<div id="collapseInstructor1" class="accordion-collapse collapse" aria-labelledby="headingInstructor1" data-bs-parent="#accordionInstructor1">
 <div class="accordion-body">
 <p>Learners can sometimes get trapped within command-line text editors
 such as Vim, Emacs, or Nano. Closing the terminal emulator and opening a
@@ -1826,15 +1826,15 @@ <h3 id="create-a-text-file">Create a text file<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> cd thesis</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="ex">$</span> nano draft.txt</span></code></pre>
 </div>
-<div id="which-editor" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="which-editor" class="callout-inner">
-<h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="which-editor">Which Editor?<a class="anchor" aria-label="anchor" href="#which-editor"></a>
 </h3>
 <div class="callout-content">
 <p>When we say, ‘<code>nano</code> is a text editor’ we really do mean
@@ -1867,12 +1867,12 @@ <h3 class="callout-title">Which Editor?<a class="anchor" aria-label="anchor" hre
 to accept the suggested default of <code>draft.txt</code>.</p>
 <p>Once our file is saved, we can use <kbd>Ctrl</kbd>+<kbd>X</kbd> to
 quit the editor and return to the shell.</p>
-<div id="control-ctrl-or-key" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="control-ctrl-or-key" class="callout-inner">
-<h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="control-ctrl-or-key">Control, Ctrl, or ^ Key<a class="anchor" aria-label="anchor" href="#control-ctrl-or-key"></a>
 </h3>
 <div class="callout-content">
 <p>The Control key is also called the ‘Ctrl’ key. There are various ways
@@ -1900,7 +1900,7 @@ <h3 class="callout-title">Control, Ctrl, or ^ Key<a class="anchor" aria-label="a
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1920,7 +1920,7 @@ <h3 class="callout-title">Creating Files a Different Way<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> touch my_file.txt</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li><p>What did the <code>touch</code> command do? When you look at your
@@ -1938,7 +1938,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>The <code>touch</code> command generates a new file called
@@ -1975,17 +1975,17 @@ <h3 class="callout-title">Creating Files a Different Way<em>(continued)</em><a c
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> rm my_file.txt</span></code></pre>
 </div>
 </div>
 </div>
 </div>
-<div id="whats-in-a-name" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="whats-in-a-name" class="callout-inner">
-<h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="whats-in-a-name">What’s In A Name?<a class="anchor" aria-label="anchor" href="#whats-in-a-name"></a>
 </h3>
 <div class="callout-content">
 <p>You may have noticed that all of Nelle’s files are named ‘something
@@ -2022,7 +2022,7 @@ <h3 class="callout-title">What’s In A Name?<a class="anchor" aria-label="ancho
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> cd ~/Desktop/shell-lesson-data/exercise-data/writing</span></code></pre>
 </div>
 <p>In our <code>thesis</code> directory we have a file
 <code>draft.txt</code> which isn’t a particularly informative name, so
@@ -2031,7 +2031,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/draft.txt thesis/quotes.txt</span></code></pre>
 </div>
 <p>The first argument tells <code>mv</code> what we’re ‘moving’, while
 the second is where it’s to go. In this case, we’re moving
@@ -2042,7 +2042,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2067,7 +2067,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> mv thesis/quotes.txt .</span></code></pre>
 </div>
 <p>The effect is to move the file from the directory it was in to the
 current working directory. <code>ls</code> now shows us that
@@ -2075,7 +2075,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> ls thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2088,7 +2088,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> ls thesis/quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2103,7 +2103,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2125,18 +2125,18 @@ <h3 class="callout-title">Moving Files to a new folder<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a> <span class="ex">analyzed/</span> raw/</span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span> analyzed</span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="ex">fructose.dat</span> glucose.dat maltose.dat sucrose.dat</span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="ex">$</span> cd analyzed</span></code></pre>
 </div>
 <p>Fill in the blanks to move these files to the <code>raw/</code>
 folder (i.e. the one she forgot to put them in)</p>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ____/____</span></code></pre>
 </div>
 </div>
 </div>
@@ -2146,12 +2146,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> mv sucrose.dat maltose.dat ../raw</span></code></pre>
 </div>
 <p>Recall that <code>..</code> refers to the parent directory (i.e. one
 above the current directory) and that <code>.</code> refers to the
@@ -2171,8 +2171,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="ex">$</span> cp quotes.txt thesis/quotations.txt</span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt thesis/quotations.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2184,14 +2184,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="at">-r</span> thesis thesis_backup</span></code></pre>
 </div>
 <p>We can check the result by listing the contents of both the
 <code>thesis</code> and <code>thesis_backup</code> directory:</p>
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> ls thesis thesis_backup</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2209,8 +2209,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> cp thesis thesis_backup</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="ex">cp:</span> <span class="at">-r</span> not specified<span class="kw">;</span> <span class="ex">omitting</span> directory <span class="st">'thesis'</span></span></code></pre>
 </div>
 <div id="renaming-files" class="callout challenge">
 <div class="callout-square">
@@ -2240,7 +2240,7 @@ <h3 class="callout-title">Renaming Files<a class="anchor" aria-label="anchor" hr
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li>No. While this would create a file with the correct name, the
@@ -2269,7 +2269,7 @@ <h3 class="callout-title">Moving and Copying<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> pwd</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2279,7 +2279,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2289,10 +2289,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
-<span id="cb41-3"><a href="#cb41-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
-<span id="cb41-4"><a href="#cb41-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> mkdir recombined</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> mv proteins.dat recombined/</span>
+<span id="cb41-3"><a href="#cb41-3" tabindex="-1"></a><span class="ex">$</span> cp recombined/proteins.dat ../proteins-saved.dat</span>
+<span id="cb41-4"><a href="#cb41-4" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li><code>proteins-saved.dat recombined</code></li>
@@ -2308,7 +2308,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We start in the <code>/Users/jamie/data</code> directory, and create
 a new folder called <code>recombined</code>. The second line moves
@@ -2347,25 +2347,25 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> rm quotes.txt</span></code></pre>
 </div>
 <p>We can confirm the file has gone using <code>ls</code>:</p>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> ls quotes.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
 <pre class="error" tabindex="0"><code>ls: cannot access 'quotes.txt': No such file or directory</code></pre>
 </div>
-<div id="deleting-is-forever" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="deleting-is-forever" class="callout-inner">
-<h3 class="callout-title">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="deleting-is-forever">Deleting Is Forever<a class="anchor" aria-label="anchor" href="#deleting-is-forever"></a>
 </h3>
 <div class="callout-content">
 <p>The Unix shell doesn’t have a trash bin that we can recover deleted
@@ -2397,7 +2397,7 @@ <h3 class="callout-title">Using<code>rm</code>Safely<a class="anchor" aria-label
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2419,7 +2419,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> rm thesis</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2434,7 +2434,7 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> rm <span class="at">-r</span> thesis</span></code></pre>
 </div>
 <p>Given that there is no way to retrieve files deleted using the shell,
 <code>rm -r</code> <em>should be used with great caution</em> (you might
@@ -2462,16 +2462,16 @@ <h3 class="callout-title">Copy with Multiple Filenames<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb49">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
-<span id="cb49-2"><a href="#cb49-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb49-1"><a href="#cb49-1" tabindex="-1"></a><span class="ex">$</span> mkdir backup</span>
+<span id="cb49-2"><a href="#cb49-2" tabindex="-1"></a><span class="ex">$</span> cp creatures/minotaur.dat creatures/unicorn.dat backup/</span></code></pre>
 </div>
 <p>In the example below, what does <code>cp</code> do when given three
 or more file names?</p>
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
-<span id="cb50-2"><a href="#cb50-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="ex">$</span> cd creatures</span>
+<span id="cb50-2"><a href="#cb50-2" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2481,7 +2481,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb52">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb52-1"><a href="#cb52-1" tabindex="-1"></a><span class="ex">$</span> cp minotaur.dat unicorn.dat basilisk.dat</span></code></pre>
 </div>
 </div>
 </div>
@@ -2491,7 +2491,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>If given more than one file name followed by a directory name
 (i.e. the destination directory must be the last argument),
@@ -2511,12 +2511,12 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="section level3">
 <h3 id="using-wildcards-for-accessing-multiple-files-at-once">Using wildcards for accessing multiple files at once<a class="anchor" aria-label="anchor" href="#using-wildcards-for-accessing-multiple-files-at-once"></a>
 </h3>
-<div id="wildcards" class="callout callout">
+<div id="callout7" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
 </h3>
 <div class="callout-content">
 <p><code>*</code> is a <strong>wildcard</strong>, which represents zero
@@ -2574,7 +2574,7 @@ <h3 class="callout-title">List filenames matching a pattern<a class="anchor" ari
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The solution is <code>3.</code></p>
 <p><code>1.</code> shows all files whose names contain zero or more
@@ -2610,25 +2610,25 @@ <h3 class="callout-title">More on Wildcards<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb54">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb54-2"><a href="#cb54-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb54-3"><a href="#cb54-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb54-4"><a href="#cb54-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb54-5"><a href="#cb54-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb54-6"><a href="#cb54-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb54-7"><a href="#cb54-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb54-8"><a href="#cb54-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb54-9"><a href="#cb54-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb54-10"><a href="#cb54-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb54-11"><a href="#cb54-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb54-12"><a href="#cb54-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb54-13"><a href="#cb54-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb54-14"><a href="#cb54-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb54-15"><a href="#cb54-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb54-16"><a href="#cb54-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb54-17"><a href="#cb54-17" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb54-18"><a href="#cb54-18" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb54-19"><a href="#cb54-19" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb54-1"><a href="#cb54-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb54-2"><a href="#cb54-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb54-3"><a href="#cb54-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb54-4"><a href="#cb54-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb54-5"><a href="#cb54-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb54-6"><a href="#cb54-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb54-7"><a href="#cb54-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb54-8"><a href="#cb54-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb54-9"><a href="#cb54-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb54-10"><a href="#cb54-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb54-11"><a href="#cb54-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb54-12"><a href="#cb54-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb54-13"><a href="#cb54-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb54-14"><a href="#cb54-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb54-15"><a href="#cb54-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb54-16"><a href="#cb54-16" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb54-17"><a href="#cb54-17" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb54-18"><a href="#cb54-18" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb54-19"><a href="#cb54-19" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span></code></pre>
 </div>
 <p>Before heading off to another field trip, she wants to back up her
 data and send some datasets to her colleague Bob. Sam uses the following
@@ -2636,57 +2636,57 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb55">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
-<span id="cb55-2"><a href="#cb55-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
-<span id="cb55-3"><a href="#cb55-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
-<span id="cb55-4"><a href="#cb55-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb55-1"><a href="#cb55-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>dataset<span class="pp">*</span> backup/datasets</span>
+<span id="cb55-2"><a href="#cb55-2" tabindex="-1"></a><span class="ex">$</span> cp ____calibration____ backup/calibration</span>
+<span id="cb55-3"><a href="#cb55-3" tabindex="-1"></a><span class="ex">$</span> cp 2015-____-____ send_to_bob/all_november_files/</span>
+<span id="cb55-4"><a href="#cb55-4" tabindex="-1"></a><span class="ex">$</span> cp ____ send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 <p>Help Sam by filling in the blanks.</p>
 <p>The resulting directory structure should look like this</p>
 <div class="codewrapper sourceCode" id="cb56">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" aria-hidden="true" tabindex="-1"></a><span class="bu">.</span></span>
-<span id="cb56-2"><a href="#cb56-2" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
-<span id="cb56-3"><a href="#cb56-3" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
-<span id="cb56-4"><a href="#cb56-4" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
-<span id="cb56-5"><a href="#cb56-5" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-6"><a href="#cb56-6" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
-<span id="cb56-7"><a href="#cb56-7" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
-<span id="cb56-8"><a href="#cb56-8" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
-<span id="cb56-9"><a href="#cb56-9" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-10"><a href="#cb56-10" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-11"><a href="#cb56-11" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-12"><a href="#cb56-12" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-13"><a href="#cb56-13" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-14"><a href="#cb56-14" aria-hidden="true" tabindex="-1"></a><span class="ex">├──</span> backup</span>
-<span id="cb56-15"><a href="#cb56-15" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
-<span id="cb56-16"><a href="#cb56-16" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
-<span id="cb56-17"><a href="#cb56-17" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
-<span id="cb56-18"><a href="#cb56-18" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
-<span id="cb56-19"><a href="#cb56-19" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
-<span id="cb56-20"><a href="#cb56-20" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-21"><a href="#cb56-21" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-22"><a href="#cb56-22" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-23"><a href="#cb56-23" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
-<span id="cb56-24"><a href="#cb56-24" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
-<span id="cb56-25"><a href="#cb56-25" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
-<span id="cb56-26"><a href="#cb56-26" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-27"><a href="#cb56-27" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-28"><a href="#cb56-28" aria-hidden="true" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-29"><a href="#cb56-29" aria-hidden="true" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
-<span id="cb56-30"><a href="#cb56-30" aria-hidden="true" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
-<span id="cb56-31"><a href="#cb56-31" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
-<span id="cb56-32"><a href="#cb56-32" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
-<span id="cb56-33"><a href="#cb56-33" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
-<span id="cb56-34"><a href="#cb56-34" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
-<span id="cb56-35"><a href="#cb56-35" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
-<span id="cb56-36"><a href="#cb56-36" aria-hidden="true" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
-<span id="cb56-37"><a href="#cb56-37" aria-hidden="true" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
-<span id="cb56-38"><a href="#cb56-38" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
-<span id="cb56-39"><a href="#cb56-39" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
-<span id="cb56-40"><a href="#cb56-40" aria-hidden="true" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
-<span id="cb56-41"><a href="#cb56-41" aria-hidden="true" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb56-1"><a href="#cb56-1" tabindex="-1"></a><span class="bu">.</span></span>
+<span id="cb56-2"><a href="#cb56-2" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-calibration.txt</span>
+<span id="cb56-3"><a href="#cb56-3" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset1.txt</span>
+<span id="cb56-4"><a href="#cb56-4" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset2.txt</span>
+<span id="cb56-5"><a href="#cb56-5" tabindex="-1"></a><span class="ex">├──</span> 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-6"><a href="#cb56-6" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-calibration.txt</span>
+<span id="cb56-7"><a href="#cb56-7" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset1.txt</span>
+<span id="cb56-8"><a href="#cb56-8" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset2.txt</span>
+<span id="cb56-9"><a href="#cb56-9" tabindex="-1"></a><span class="ex">├──</span> 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-10"><a href="#cb56-10" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-11"><a href="#cb56-11" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-12"><a href="#cb56-12" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-13"><a href="#cb56-13" tabindex="-1"></a><span class="ex">├──</span> 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-14"><a href="#cb56-14" tabindex="-1"></a><span class="ex">├──</span> backup</span>
+<span id="cb56-15"><a href="#cb56-15" tabindex="-1"></a><span class="ex">│  </span> ├── calibration</span>
+<span id="cb56-16"><a href="#cb56-16" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-23-calibration.txt</span>
+<span id="cb56-17"><a href="#cb56-17" tabindex="-1"></a><span class="ex">│  </span> │   ├── 2015-10-26-calibration.txt</span>
+<span id="cb56-18"><a href="#cb56-18" tabindex="-1"></a><span class="ex">│  </span> │   └── 2015-11-23-calibration.txt</span>
+<span id="cb56-19"><a href="#cb56-19" tabindex="-1"></a><span class="ex">│  </span> └── datasets</span>
+<span id="cb56-20"><a href="#cb56-20" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-21"><a href="#cb56-21" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-22"><a href="#cb56-22" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-23"><a href="#cb56-23" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset1.txt</span>
+<span id="cb56-24"><a href="#cb56-24" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset2.txt</span>
+<span id="cb56-25"><a href="#cb56-25" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-10-26-dataset_overview.txt</span>
+<span id="cb56-26"><a href="#cb56-26" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-27"><a href="#cb56-27" tabindex="-1"></a><span class="ex">│  </span>     ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-28"><a href="#cb56-28" tabindex="-1"></a><span class="ex">│  </span>     └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-29"><a href="#cb56-29" tabindex="-1"></a><span class="ex">└──</span> send_to_bob</span>
+<span id="cb56-30"><a href="#cb56-30" tabindex="-1"></a>    <span class="ex">├──</span> all_datasets_created_on_a_23rd</span>
+<span id="cb56-31"><a href="#cb56-31" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset1.txt</span>
+<span id="cb56-32"><a href="#cb56-32" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset2.txt</span>
+<span id="cb56-33"><a href="#cb56-33" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-10-23-dataset_overview.txt</span>
+<span id="cb56-34"><a href="#cb56-34" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset1.txt</span>
+<span id="cb56-35"><a href="#cb56-35" tabindex="-1"></a>    <span class="ex">│  </span> ├── 2015-11-23-dataset2.txt</span>
+<span id="cb56-36"><a href="#cb56-36" tabindex="-1"></a>    <span class="ex">│  </span> └── 2015-11-23-dataset_overview.txt</span>
+<span id="cb56-37"><a href="#cb56-37" tabindex="-1"></a>    <span class="ex">└──</span> all_november_files</span>
+<span id="cb56-38"><a href="#cb56-38" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-calibration.txt</span>
+<span id="cb56-39"><a href="#cb56-39" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset1.txt</span>
+<span id="cb56-40"><a href="#cb56-40" tabindex="-1"></a>        <span class="ex">├──</span> 2015-11-23-dataset2.txt</span>
+<span id="cb56-41"><a href="#cb56-41" tabindex="-1"></a>        <span class="ex">└──</span> 2015-11-23-dataset_overview.txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -2696,14 +2696,14 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb57">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
-<span id="cb57-2"><a href="#cb57-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
-<span id="cb57-3"><a href="#cb57-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb57-1"><a href="#cb57-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>calibration.txt backup/calibration</span>
+<span id="cb57-2"><a href="#cb57-2" tabindex="-1"></a><span class="ex">$</span> cp 2015-11-<span class="pp">*</span> send_to_bob/all_november_files/</span>
+<span id="cb57-3"><a href="#cb57-3" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>-23-dataset<span class="pp">*</span> send_to_bob/all_datasets_created_on_a_23rd/</span></code></pre>
 </div>
 </div>
 </div>
@@ -2722,7 +2722,7 @@ <h3 class="callout-title">Organizing Directories and Files<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb58">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb58-1"><a href="#cb58-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2736,7 +2736,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb60">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb60-1"><a href="#cb60-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="at">-F</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2746,7 +2746,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb62">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb62-1"><a href="#cb62-1" tabindex="-1"></a><span class="ex">$</span> ls analyzed</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2761,12 +2761,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
   <h4 class="accordion-header" id="headingSolution9">Show me the solution</h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb64">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" aria-hidden="true" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb64-1"><a href="#cb64-1" tabindex="-1"></a><span class="fu">mv</span> <span class="pp">*</span>.dat analyzed</span></code></pre>
 </div>
 <p>Jamie needs to move her files <code>fructose.dat</code> and
 <code>sucrose.dat</code> to the <code>analyzed</code> directory. The
@@ -2808,39 +2808,39 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb66-2"><a href="#cb66-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
-<span id="cb66-3"><a href="#cb66-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
-<span id="cb66-4"><a href="#cb66-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb66-1"><a href="#cb66-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb66-2"><a href="#cb66-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data</span>
+<span id="cb66-3"><a href="#cb66-3" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span>
+<span id="cb66-4"><a href="#cb66-4" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span></code></pre>
 </div>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb67-2"><a href="#cb67-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb67-3"><a href="#cb67-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb67-4"><a href="#cb67-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd data</span>
-<span id="cb67-5"><a href="#cb67-5" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb67-1"><a href="#cb67-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb67-2"><a href="#cb67-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb67-3"><a href="#cb67-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb67-4"><a href="#cb67-4" tabindex="-1"></a><span class="ex">$</span> cd data</span>
+<span id="cb67-5"><a href="#cb67-5" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb68">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
-<span id="cb68-2"><a href="#cb68-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb68-1"><a href="#cb68-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/raw</span>
+<span id="cb68-2"><a href="#cb68-2" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20/data/processed</span></code></pre>
 </div>
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
-<span id="cb69-2"><a href="#cb69-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb69-1"><a href="#cb69-1" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/raw</span>
+<span id="cb69-2"><a href="#cb69-2" tabindex="-1"></a><span class="ex">$</span> mkdir <span class="at">-p</span> 2016-05-20/data/processed</span></code></pre>
 </div>
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
-<span id="cb70-2"><a href="#cb70-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
-<span id="cb70-3"><a href="#cb70-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
-<span id="cb70-4"><a href="#cb70-4" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb70-1"><a href="#cb70-1" tabindex="-1"></a><span class="ex">$</span> mkdir 2016-05-20</span>
+<span id="cb70-2"><a href="#cb70-2" tabindex="-1"></a><span class="ex">$</span> cd 2016-05-20</span>
+<span id="cb70-3"><a href="#cb70-3" tabindex="-1"></a><span class="ex">$</span> mkdir data</span>
+<span id="cb70-4"><a href="#cb70-4" tabindex="-1"></a><span class="ex">$</span> mkdir raw processed</span></code></pre>
 </div>
 </div>
 </div>
@@ -2850,7 +2850,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Show me the solution</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <p>The first two sets of commands achieve this objective. The first set
 uses relative paths to create the top-level directory before the
@@ -2958,7 +2958,7 @@ <h3 class="card-title">Objectives</h3>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> ls</span></code></pre>
 </div>
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> wc cubane.pdb</span></code></pre>
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@@ -2987,7 +2987,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="pp">*</span>.pdb</span></code></pre>
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@@ -3007,7 +3007,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb</span></code></pre>
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@@ -3023,12 +3023,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <p>The <code>-m</code> and <code>-w</code> options can also be used with
 the <code>wc</code> command to show only the number of characters or the
 number of words, respectively.</p>
-<div id="why-isnt-it-doing-anything" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="why-isnt-it-doing-anything" class="callout-inner">
-<h3 class="callout-title">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="why-isnt-it-doing-anything">Why Isn’t It Doing Anything?<a class="anchor" aria-label="anchor" href="#why-isnt-it-doing-anything"></a>
 </h3>
 <div class="callout-content">
 <p>What happens if a command is supposed to process a file, but we don’t
@@ -3036,7 +3036,7 @@ <h3 class="callout-title">Why Isn’t It Doing Anything?<a class="anchor" aria-l
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span></span></code></pre>
 </div>
 <p>but don’t type <code>*.pdb</code> (or anything else) after the
 command? Since it doesn’t have any filenames, <code>wc</code> assumes it
@@ -3060,7 +3060,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>The greater than symbol, <code>&gt;</code>, tells the shell to
 <strong>redirect</strong> the command’s output to a file instead of
@@ -3074,7 +3074,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> ls lengths.txt</span></code></pre>
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@@ -3089,7 +3089,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> cat lengths.txt</span></code></pre>
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@@ -3102,12 +3102,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
   15  propane.pdb
  107  total</code></pre>
 </div>
-<div id="output-page-by-page" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="output-page-by-page" class="callout-inner">
-<h3 class="callout-title">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="output-page-by-page">Output Page by Page<a class="anchor" aria-label="anchor" href="#output-page-by-page"></a>
 </h3>
 <div class="callout-content">
 <p>We’ll continue to use <code>cat</code> in this lesson, for
@@ -3171,7 +3171,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>The <code>-n</code> option specifies a numerical rather than an
 alphanumerical sort.</p>
@@ -3185,7 +3185,7 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt</span></code></pre>
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@@ -3208,8 +3208,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
-<span id="cb20-2"><a href="#cb20-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> sorted-lengths.txt</span>
+<span id="cb20-2"><a href="#cb20-2" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 sorted-lengths.txt</span></code></pre>
 </div>
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@@ -3221,12 +3221,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 20, and so on. Since <code>sorted-lengths.txt</code> contains the
 lengths of our files ordered from least to greatest, the output of
 <code>head</code> must be the file with the fewest lines.</p>
-<div id="redirecting-to-the-same-file" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="redirecting-to-the-same-file" class="callout-inner">
-<h3 class="callout-title">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="redirecting-to-the-same-file">Redirecting to the same file<a class="anchor" aria-label="anchor" href="#redirecting-to-the-same-file"></a>
 </h3>
 <div class="callout-content">
 <p>It’s a very bad idea to try redirecting the output of a command that
@@ -3234,7 +3234,7 @@ <h3 class="callout-title">Redirecting to the same file<a class="anchor" aria-lab
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="op">&gt;</span> lengths.txt</span></code></pre>
 </div>
 <p>Doing something like this may give you incorrect results and/or
 delete the contents of <code>lengths.txt</code>.</p>
@@ -3257,7 +3257,7 @@ <h3 class="callout-title">What Does<code>&gt;&gt;</code>Mean?<a class="anchor" a
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-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb23-1"><a href="#cb23-1" tabindex="-1"></a><span class="ex">$</span> echo The echo command prints text</span></code></pre>
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@@ -3269,13 +3269,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;</span> testfile01.txt</span></code></pre>
 </div>
 <p>and:</p>
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> echo hello <span class="op">&gt;&gt;</span> testfile02.txt</span></code></pre>
 </div>
 <p>Hint: Try executing each command twice in a row and then examining
 the output files.</p>
@@ -3287,7 +3287,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>In the first example with <code>&gt;</code>, the string ‘hello’ is
 written to <code>testfile01.txt</code>, but the file gets overwritten
@@ -3318,8 +3318,8 @@ <h3 class="callout-title">Appending Data<a class="anchor" aria-label="anchor" hr
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
-<span id="cb27-2"><a href="#cb27-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 3 animals.csv <span class="op">&gt;</span> animals-subset.csv</span>
+<span id="cb27-2"><a href="#cb27-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 2 animals.csv <span class="op">&gt;&gt;</span> animals-subset.csv</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>The first three lines of <code>animals.csv</code>
@@ -3340,7 +3340,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Option 3 is correct. For option 1 to be correct we would only run the
 <code>head</code> command. For option 2 to be correct we would only run
@@ -3366,7 +3366,7 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> sort <span class="at">-n</span> lengths.txt <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3391,7 +3391,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3409,7 +3409,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3446,7 +3446,7 @@ <h3 class="callout-title">Piping Commands Together<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Option 4 is the solution. The pipe character <code>|</code> is used
 to connect the output from one command to the input of another.
@@ -3500,7 +3500,7 @@ <h3 class="callout-title">Pipe Reading Comprehension<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="ex">$</span> cat animals.csv <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5 <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 3 <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-r</span> <span class="op">&gt;</span> final.txt</span></code></pre>
 </div>
 <p>Hint: build the pipeline up one command at a time to test your
 understanding</p>
@@ -3512,7 +3512,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>The <code>head</code> command extracts the first 5 lines from
 <code>animals.csv</code>. Then, the last 3 lines are extracted from the
@@ -3542,7 +3542,7 @@ <h3 class="callout-title">Pipe Construction<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv</span></code></pre>
 </div>
 <p>The <code>cut</code> command is used to remove or ‘cut out’ certain
 sections of each line in the file, and <code>cut</code> expects the
@@ -3576,12 +3576,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> cut <span class="at">-d</span> , <span class="at">-f</span> 2 animals.csv <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -3627,7 +3627,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
 <div class="accordion-body">
 <p>Option 4. is the correct answer. If you have difficulty understanding
 why, try running the commands, or sub-sections of the pipelines (make
@@ -3648,8 +3648,8 @@ <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="ex">$</span> cd north-pacific-gyre</span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <p>The output is 18 lines that look like this:</p>
 <div class="codewrapper">
@@ -3667,7 +3667,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3686,7 +3686,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.txt <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3704,7 +3704,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> ls <span class="pp">*</span>Z.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3745,7 +3745,7 @@ <h3 class="callout-title">Removing Unneeded Files<a class="anchor" aria-label="a
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>This would remove <code>.txt</code> files with one-character
@@ -3857,7 +3857,7 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 5 basilisk.dat minotaur.dat unicorn.dat</span></code></pre>
 </div>
 <p>We would like to print out the classification for each species, which
 is given on the second line of each file. For each file, we would need
@@ -3868,24 +3868,24 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
-<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
-<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span> </span>
-<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
-<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
-<span id="cb2-7"><a href="#cb2-7" aria-hidden="true" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
-<span id="cb2-8"><a href="#cb2-8" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="co"># The word "for" indicates the start of a "For-loop" command</span></span>
+<span id="cb2-2"><a href="#cb2-2" tabindex="-1"></a><span class="cf">for</span> thing <span class="kw">in</span> list_of_things </span>
+<span id="cb2-3"><a href="#cb2-3" tabindex="-1"></a><span class="co">#The word "do" indicates the start of job execution list</span></span>
+<span id="cb2-4"><a href="#cb2-4" tabindex="-1"></a><span class="cf">do</span> </span>
+<span id="cb2-5"><a href="#cb2-5" tabindex="-1"></a>    <span class="co"># Indentation within the loop is not required, but aids legibility</span></span>
+<span id="cb2-6"><a href="#cb2-6" tabindex="-1"></a>    <span class="ex">operation_using/command</span> <span class="va">$thing</span> </span>
+<span id="cb2-7"><a href="#cb2-7" tabindex="-1"></a><span class="co"># The word "done" indicates the end of a loop</span></span>
+<span id="cb2-8"><a href="#cb2-8" tabindex="-1"></a><span class="cf">done</span>  </span></code></pre>
 </div>
 <p>and we can apply this to our example like this:</p>
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> for filename in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb3-3"><a href="#cb3-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb3-4"><a href="#cb3-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb3-5"><a href="#cb3-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3897,12 +3897,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 unicorn.dat
 CLASSIFICATION: equus monoceros</code></pre>
 </div>
-<div id="follow-the-prompt" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="follow-the-prompt" class="callout-inner">
-<h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="follow-the-prompt">Follow the Prompt<a class="anchor" aria-label="anchor" href="#follow-the-prompt"></a>
 </h3>
 <div class="callout-content">
 <p>The shell prompt changes from <code>$</code> to <code>&gt;</code> and
@@ -3943,12 +3943,12 @@ <h3 class="callout-title">Follow the Prompt<a class="anchor" aria-label="anchor"
 runs the <code>head</code> command on that file, and <code>tail</code>
 on the output of that. Since the list was only three items, the shell
 exits the <code>for</code> loop.</p>
-<div id="same-symbols-different-meanings" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="same-symbols-different-meanings" class="callout-inner">
-<h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="same-symbols-different-meanings">Same Symbols, Different Meanings<a class="anchor" aria-label="anchor" href="#same-symbols-different-meanings"></a>
 </h3>
 <div class="callout-content">
 <p>Here we see <code>&gt;</code> being used as a shell prompt, whereas
@@ -3974,19 +3974,19 @@ <h3 class="callout-title">Same Symbols, Different Meanings<a class="anchor" aria
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> for x in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb5-2"><a href="#cb5-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb5-3"><a href="#cb5-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$x</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb5-4"><a href="#cb5-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>or:</p>
 <div class="codewrapper sourceCode" id="cb6">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
-<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
-<span id="cb6-4"><a href="#cb6-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" tabindex="-1"></a><span class="ex">$</span> for temperature in basilisk.dat minotaur.dat unicorn.dat</span>
+<span id="cb6-2"><a href="#cb6-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb6-3"><a href="#cb6-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 2 <span class="va">$temperature</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 1</span>
+<span id="cb6-4"><a href="#cb6-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>it would work exactly the same way. <em>Don’t do this.</em> Programs
 are only useful if people can understand them, so meaningless names
@@ -4017,15 +4017,15 @@ <h3 class="callout-title">Write your own loop<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
-<span id="cb7-2"><a href="#cb7-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb7-3"><a href="#cb7-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
-<span id="cb7-4"><a href="#cb7-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> for loop_variable in 0 1 2 3 4 5 6 7 8 9</span>
+<span id="cb7-2"><a href="#cb7-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb7-3"><a href="#cb7-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$loop_variable</span></span>
+<span id="cb7-4"><a href="#cb7-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4065,19 +4065,19 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb10">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb10-2"><a href="#cb10-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb10-3"><a href="#cb10-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
-<span id="cb10-4"><a href="#cb10-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb10-1"><a href="#cb10-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb10-2"><a href="#cb10-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb10-3"><a href="#cb10-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">*.pdb</span></span>
+<span id="cb10-4"><a href="#cb10-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Now, what is the output of the following code?</p>
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb11-2"><a href="#cb11-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb11-3"><a href="#cb11-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
-<span id="cb11-4"><a href="#cb11-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$datafile</span></span>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>Why do these two loops give different outputs?</p>
 </div>
@@ -4088,7 +4088,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>The first code block gives the same output on each iteration through
 the loop. Bash expands the wildcard <code>*.pdb</code> within the loop
@@ -4098,10 +4098,10 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb12">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-2"><a href="#cb12-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb12-3"><a href="#cb12-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
-<span id="cb12-4"><a href="#cb12-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb12-1"><a href="#cb12-1" tabindex="-1"></a><span class="ex">$</span> for datafile in cubane.pdb  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-2"><a href="#cb12-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb12-3"><a href="#cb12-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="ex">cubane.pdb</span>  ethane.pdb  methane.pdb  octane.pdb  pentane.pdb  propane.pdb</span>
+<span id="cb12-4"><a href="#cb12-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4143,10 +4143,10 @@ <h3 class="callout-title">Limiting Sets of Files<a class="anchor" aria-label="an
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
-<span id="cb15-2"><a href="#cb15-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb15-3"><a href="#cb15-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb15-4"><a href="#cb15-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> for filename in c<span class="pp">*</span></span>
+<span id="cb15-2"><a href="#cb15-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb15-3"><a href="#cb15-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb15-4"><a href="#cb15-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>No files are listed.</li>
@@ -4163,7 +4163,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so any file name starting with the letter c, followed by
@@ -4184,10 +4184,10 @@ <h3 class="callout-title">Limiting Sets of Files<em>(continued)</em><a class="an
 <div class="codewrapper sourceCode" id="cb16">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
-<span id="cb16-2"><a href="#cb16-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb16-3"><a href="#cb16-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
-<span id="cb16-4"><a href="#cb16-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb16-1"><a href="#cb16-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>c<span class="pp">*</span></span>
+<span id="cb16-2"><a href="#cb16-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb16-3"><a href="#cb16-3" tabindex="-1"></a><span class="op">&gt;</span>     ls <span class="va">$filename</span></span>
+<span id="cb16-4"><a href="#cb16-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>The same files would be listed.</li>
@@ -4205,7 +4205,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>4 is the correct answer. <code>*</code> matches zero or more
 characters, so a file name with zero or more characters before a letter
@@ -4227,11 +4227,11 @@ <h3 class="callout-title">Saving to a File in a Loop - Part One<a class="anchor"
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb17-2"><a href="#cb17-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb17-3"><a href="#cb17-3" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
-<span id="cb17-4"><a href="#cb17-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
-<span id="cb17-5"><a href="#cb17-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="cf">for</span> alkanes <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb17-2"><a href="#cb17-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb17-3"><a href="#cb17-3" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$alkanes</span></span>
+<span id="cb17-4"><a href="#cb17-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$alkanes</span> <span class="op">&gt;</span> alkanes.pdb</span>
+<span id="cb17-5"><a href="#cb17-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>Prints <code>cubane.pdb</code>, <code>ethane.pdb</code>,
@@ -4256,7 +4256,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li>The text from each file in turn gets written to the
@@ -4281,10 +4281,10 @@ <h3 class="callout-title">Saving to a File in a Loop - Part Two<a class="anchor"
 <div class="codewrapper sourceCode" id="cb18">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
-<span id="cb18-2"><a href="#cb18-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb18-3"><a href="#cb18-3" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb18-4"><a href="#cb18-4" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb18-1"><a href="#cb18-1" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="pp">*</span>.pdb</span>
+<span id="cb18-2"><a href="#cb18-2" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb18-3"><a href="#cb18-3" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb18-4"><a href="#cb18-4" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <ol style="list-style-type: decimal">
 <li>All of the text from <code>cubane.pdb</code>,
@@ -4312,7 +4312,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>3 is the correct answer. <code>&gt;&gt;</code> appends to a file,
 rather than overwriting it with the redirected output from a command.
@@ -4328,11 +4328,11 @@ <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb19-2"><a href="#cb19-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb19-3"><a href="#cb19-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
-<span id="cb19-4"><a href="#cb19-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb19-5"><a href="#cb19-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb19-2"><a href="#cb19-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb19-3"><a href="#cb19-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$filename</span></span>
+<span id="cb19-4"><a href="#cb19-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb19-5"><a href="#cb19-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>The shell starts by expanding <code>*.dat</code> to create the list
 of files it will process. The <strong>loop body</strong> then executes
@@ -4342,7 +4342,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> echo hello there</span></code></pre>
 </div>
 <p>prints:</p>
 <div class="codewrapper">
@@ -4356,11 +4356,11 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb22-2"><a href="#cb22-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb22-3"><a href="#cb22-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
-<span id="cb22-4"><a href="#cb22-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb22-5"><a href="#cb22-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb22-2"><a href="#cb22-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb22-3"><a href="#cb22-3" tabindex="-1"></a><span class="op">&gt;</span>     <span class="va">$filename</span></span>
+<span id="cb22-4"><a href="#cb22-4" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="va">$filename</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb22-5"><a href="#cb22-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>because then the first time through the loop, when
 <code>$filename</code> expanded to <code>basilisk.dat</code>, the shell
@@ -4368,12 +4368,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <code>head</code> and <code>tail</code> combination selects lines 81-100
 from whatever file is being processed (assuming the file has at least
 100 lines).</p>
-<div id="spaces-in-names" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="spaces-in-names" class="callout-inner">
-<h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="spaces-in-names">Spaces in Names<a class="anchor" aria-label="anchor" href="#spaces-in-names"></a>
 </h3>
 <div class="callout-content">
 <p>Spaces are used to separate the elements of the list that we are
@@ -4387,10 +4387,10 @@ <h3 class="callout-title">Spaces in Names<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
-<span id="cb24-2"><a href="#cb24-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb24-3"><a href="#cb24-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
-<span id="cb24-4"><a href="#cb24-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="st">"red dragon.dat"</span> <span class="st">"purple unicorn.dat"</span></span>
+<span id="cb24-2"><a href="#cb24-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb24-3"><a href="#cb24-3" tabindex="-1"></a><span class="op">&gt;</span>     head <span class="ex">-n</span> 100 <span class="st">"</span><span class="va">$filename</span><span class="st">"</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 20</span>
+<span id="cb24-4"><a href="#cb24-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>It is simpler to avoid using spaces (or other special characters) in
 filenames.</p>
@@ -4430,13 +4430,13 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb27">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb27-1"><a href="#cb27-1" tabindex="-1"></a><span class="ex">$</span> cp <span class="pp">*</span>.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>because that would expand to:</p>
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> cp basilisk.dat minotaur.dat unicorn.dat original-<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <p>This wouldn’t back up our files, instead we get an error:</p>
 <div class="codewrapper">
@@ -4453,10 +4453,10 @@ <h3 class="code-label">ERROR<i aria-hidden="true" data-feather="chevron-left"></
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
-<span id="cb30-2"><a href="#cb30-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb30-3"><a href="#cb30-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
-<span id="cb30-4"><a href="#cb30-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> for filename in <span class="pp">*</span>.dat</span>
+<span id="cb30-2"><a href="#cb30-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb30-3"><a href="#cb30-3" tabindex="-1"></a><span class="op">&gt;</span>     cp <span class="va">$filename</span> original-<span class="va">$filename</span></span>
+<span id="cb30-4"><a href="#cb30-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>This loop runs the <code>cp</code> command once for each filename.
 The first time, when <code>$filename</code> expands to
@@ -4464,19 +4464,19 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="fu">cp</span> basilisk.dat original-basilisk.dat</span></code></pre>
 </div>
 <p>The second time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="fu">cp</span> minotaur.dat original-minotaur.dat</span></code></pre>
 </div>
 <p>The third and last time, the command is:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="fu">cp</span> unicorn.dat original-unicorn.dat</span></code></pre>
 </div>
 <p>Since the <code>cp</code> command does not normally produce any
 output, it’s hard to check that the loop is working correctly. However,
@@ -4506,12 +4506,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/north-pacific-gyre</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4530,10 +4530,10 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb36-2"><a href="#cb36-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb36-3"><a href="#cb36-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb36-4"><a href="#cb36-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb36-2"><a href="#cb36-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb36-3"><a href="#cb36-3" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb36-4"><a href="#cb36-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4556,14 +4556,14 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>Using the <kbd>←</kbd>, Nelle navigates to the <code>echo</code>
 command and changes it to <code>bash goostats.sh</code>:</p>
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
 <p>When she presses <kbd>Enter</kbd>, the shell runs the modified
 command. However, nothing appears to happen — there is no output. After
@@ -4575,15 +4575,15 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> for datafile in NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt<span class="kw">;</span> <span class="cf">do</span> <span class="bu">echo</span> <span class="va">$datafile</span><span class="kw">;</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre>
 </div>
-<div id="beginning-and-end" class="callout callout">
+<div id="callout4" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="beginning-and-end" class="callout-inner">
-<h3 class="callout-title">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="beginning-and-end">Beginning and End<a class="anchor" aria-label="anchor" href="#beginning-and-end"></a>
 </h3>
 <div class="callout-content">
 <p>We can move to the beginning of a line in the shell by typing
@@ -4608,12 +4608,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <code>cat stats-NENE01729B.txt</code> to examine one of the output
 files. It looks good, so she decides to get some coffee and catch up on
 her reading.</p>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout callout">
+<div id="callout5" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="those-who-know-history-can-choose-to-repeat-it" class="callout-inner">
-<h3 class="callout-title">Those Who Know History Can Choose to Repeat
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="those-who-know-history-can-choose-to-repeat-it">Those Who Know History Can Choose to Repeat
 It<a class="anchor" aria-label="anchor" href="#those-who-know-history-can-choose-to-repeat-it"></a>
 </h3>
 <div class="callout-content">
@@ -4625,7 +4625,7 @@ <h3 class="callout-title">Those Who Know History Can Choose to Repeat
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4642,12 +4642,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 </div>
 </div>
-<div id="other-history-commands" class="callout callout">
+<div id="callout6" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="other-history-commands" class="callout-inner">
-<h3 class="callout-title">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="other-history-commands">Other History Commands<a class="anchor" aria-label="anchor" href="#other-history-commands"></a>
 </h3>
 <div class="callout-content">
 <p>There are a number of other shortcut commands for getting at the
@@ -4691,30 +4691,30 @@ <h3 class="callout-title">Doing a Dry Run<a class="anchor" aria-label="anchor" h
 <div class="codewrapper sourceCode" id="cb44">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb44-2"><a href="#cb44-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb44-3"><a href="#cb44-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb44-4"><a href="#cb44-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb44-1"><a href="#cb44-1" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb44-2"><a href="#cb44-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb44-3"><a href="#cb44-3" tabindex="-1"></a><span class="op">&gt;</span>     cat <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb44-4"><a href="#cb44-4" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <p>What is the difference between the two loops below, and which one
 would we want to run?</p>
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 1</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Version 1</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="fu">cat</span> <span class="va">$datafile</span> <span class="op">&gt;&gt;</span> all.pdb</span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Version 2</span></span>
-<span id="cb46-2"><a href="#cb46-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
-<span id="cb46-3"><a href="#cb46-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb46-4"><a href="#cb46-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
-<span id="cb46-5"><a href="#cb46-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="co"># Version 2</span></span>
+<span id="cb46-2"><a href="#cb46-2" tabindex="-1"></a><span class="ex">$</span> for datafile in <span class="pp">*</span>.pdb</span>
+<span id="cb46-3"><a href="#cb46-3" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb46-4"><a href="#cb46-4" tabindex="-1"></a><span class="op">&gt;</span>     echo <span class="st">"cat </span><span class="va">$datafile</span><span class="st"> &gt;&gt; all.pdb"</span></span>
+<span id="cb46-5"><a href="#cb46-5" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -4724,7 +4724,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Show me the solution</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The second version is the one we want to run. This prints to screen
 everything enclosed in the quote marks, expanding the loop variable name
@@ -4757,13 +4757,13 @@ <h3 class="callout-title">Nested Loops<a class="anchor" aria-label="anchor" href
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
-<span id="cb47-2"><a href="#cb47-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> do</span>
-<span id="cb47-3"><a href="#cb47-3" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
-<span id="cb47-4"><a href="#cb47-4" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
-<span id="cb47-5"><a href="#cb47-5" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
-<span id="cb47-6"><a href="#cb47-6" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
-<span id="cb47-7"><a href="#cb47-7" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> for species in cubane ethane methane</span>
+<span id="cb47-2"><a href="#cb47-2" tabindex="-1"></a><span class="op">&gt;</span> do</span>
+<span id="cb47-3"><a href="#cb47-3" tabindex="-1"></a><span class="op">&gt;</span>     for <span class="ex">temperature</span> in 25 30 37 40</span>
+<span id="cb47-4"><a href="#cb47-4" tabindex="-1"></a><span class="op">&gt;</span>     do</span>
+<span id="cb47-5"><a href="#cb47-5" tabindex="-1"></a><span class="op">&gt;</span>         mkdir <span class="va">$species</span><span class="ex">-</span><span class="va">$temperature</span></span>
+<span id="cb47-6"><a href="#cb47-6" tabindex="-1"></a><span class="op">&gt;</span>     done</span>
+<span id="cb47-7"><a href="#cb47-7" tabindex="-1"></a><span class="op">&gt;</span> done</span></code></pre>
 </div>
 </div>
 </div>
@@ -4773,7 +4773,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Show me the solution</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <p>We have a nested loop, i.e. contained within another loop, so for
 each species in the outer loop, the inner loop (the nested loop)
@@ -4873,8 +4873,8 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd alkanes</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>The command <code>nano middle.sh</code> opens the file
 <code>middle.sh</code> within the text editor ‘nano’ (which runs within
@@ -4896,7 +4896,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4909,12 +4909,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 </div>
 <p>Sure enough, our script’s output is exactly what we would get if we
 ran that pipeline directly.</p>
-<div id="text-vs.-whatever" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="text-vs.-whatever" class="callout-inner">
-<h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs.-whatever"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="text-vs--whatever">Text vs. Whatever<a class="anchor" aria-label="anchor" href="#text-vs--whatever"></a>
 </h3>
 <div class="callout-content">
 <p>We usually call programs like Microsoft Word or LibreOffice Writer
@@ -4938,7 +4938,7 @@ <h3 class="callout-title">Text vs. Whatever<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <p>Now, within “nano”, replace the text <code>octane.pdb</code> with the
 special variable called <code>$1</code>:</p>
@@ -4949,7 +4949,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh octane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4964,7 +4964,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4975,12 +4975,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 ATOM     12  H           1      -0.048  -1.362  -0.205  1.00  0.00
 ATOM     13  H           1      -1.183   0.500  -1.412  1.00  0.00</code></pre>
 </div>
-<div id="double-quotes-around-arguments" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="double-quotes-around-arguments" class="callout-inner">
-<h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="double-quotes-around-arguments">Double-Quotes Around Arguments<a class="anchor" aria-label="anchor" href="#double-quotes-around-arguments"></a>
 </h3>
 <div class="callout-content">
 <p>For the same reason that we put the loop variable inside
@@ -5002,14 +5002,14 @@ <h3 class="callout-title">Double-Quotes Around Arguments<a class="anchor" aria-l
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code>head -n "$2" "$1" | tail -n "$3"</code></pre>
 <p>We can now run:</p>
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 15 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5025,7 +5025,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> bash middle.sh pentane.pdb 20 5</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5043,7 +5043,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> nano middle.sh</span></code></pre>
 </div>
 <pre class="source"><code># Select lines from the middle of a file.
 # Usage: bash middle.sh filename end_line num_lines
@@ -5060,7 +5060,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="pp">*</span>.pdb <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 <p>because <code>wc -l</code> lists the number of lines in the files
 (recall that <code>wc</code> stands for ‘word count’, adding the
@@ -5080,7 +5080,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb20">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb20-1"><a href="#cb20-1" tabindex="-1"></a><span class="ex">$</span> nano sorted.sh</span></code></pre>
 </div>
 <pre class="source"><code># Sort files by their length.
 # Usage: bash sorted.sh one_or_more_filenames
@@ -5088,7 +5088,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb22">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb22-1"><a href="#cb22-1" tabindex="-1"></a><span class="ex">$</span> bash sorted.sh <span class="pp">*</span>.pdb ../creatures/<span class="pp">*</span>.dat</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5141,21 +5141,21 @@ <h3 class="callout-title">List Unique Species<a class="anchor" aria-label="ancho
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb25">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
-<span id="cb25-2"><a href="#cb25-2" aria-hidden="true" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
-<span id="cb25-3"><a href="#cb25-3" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb25-4"><a href="#cb25-4" aria-hidden="true" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
-<span id="cb25-5"><a href="#cb25-5" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
-<span id="cb25-6"><a href="#cb25-6" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb25-7"><a href="#cb25-7" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
-<span id="cb25-8"><a href="#cb25-8" aria-hidden="true" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
-<span id="cb25-9"><a href="#cb25-9" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
-<span id="cb25-10"><a href="#cb25-10" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb25-1"><a href="#cb25-1" tabindex="-1"></a><span class="co"># Script to find unique species in csv files where species is the second data field</span></span>
+<span id="cb25-2"><a href="#cb25-2" tabindex="-1"></a><span class="co"># This script accepts any number of file names as command line arguments</span></span>
+<span id="cb25-3"><a href="#cb25-3" tabindex="-1"></a></span>
+<span id="cb25-4"><a href="#cb25-4" tabindex="-1"></a><span class="co"># Loop over all files</span></span>
+<span id="cb25-5"><a href="#cb25-5" tabindex="-1"></a><span class="cf">for</span> file <span class="kw">in</span> <span class="va">$@</span></span>
+<span id="cb25-6"><a href="#cb25-6" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb25-7"><a href="#cb25-7" tabindex="-1"></a>    <span class="bu">echo</span> <span class="st">"Unique species in </span><span class="va">$file</span><span class="st">:"</span></span>
+<span id="cb25-8"><a href="#cb25-8" tabindex="-1"></a>    <span class="co"># Extract species names</span></span>
+<span id="cb25-9"><a href="#cb25-9" tabindex="-1"></a>    <span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 2 <span class="va">$file</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="kw">|</span> <span class="fu">uniq</span></span>
+<span id="cb25-10"><a href="#cb25-10" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -5169,7 +5169,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb26">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb26-1"><a href="#cb26-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> redo-figure-3.sh</span></code></pre>
 </div>
 <p>The file <code>redo-figure-3.sh</code> now contains:</p>
 <pre class="source"><code>297 bash goostats.sh NENE01729B.txt stats-NENE01729B.txt
@@ -5194,7 +5194,7 @@ <h3 class="callout-title">Why Record Commands in the History Before
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="ex">$</span> history <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 5 <span class="op">&gt;</span> recent.sh</span></code></pre>
 </div>
 <p>the last command in the file is the <code>history</code> command
 itself, i.e., the shell has added <code>history</code> to the command
@@ -5209,7 +5209,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>If a command causes something to crash or hang, it might be useful to
 know what that command was, in order to investigate the problem. Were
@@ -5235,37 +5235,37 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb29">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb29-1"><a href="#cb29-1" tabindex="-1"></a><span class="ex">$</span> cd ../../north-pacific-gyre/</span></code></pre>
 </div>
 <p>She creates a file using <code>nano</code> …</p>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> nano do-stats.sh</span></code></pre>
 </div>
 <p>…which contains the following:</p>
 <div class="codewrapper sourceCode" id="cb31">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb31-2"><a href="#cb31-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb31-3"><a href="#cb31-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb31-4"><a href="#cb31-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb31-5"><a href="#cb31-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb31-6"><a href="#cb31-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb31-1"><a href="#cb31-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb31-2"><a href="#cb31-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb31-3"><a href="#cb31-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb31-4"><a href="#cb31-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb31-5"><a href="#cb31-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb31-6"><a href="#cb31-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>She saves this in a file called <code>do-stats.sh</code> so that she
 can now re-do the first stage of her analysis by typing:</p>
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb32-1"><a href="#cb32-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>She can also do this:</p>
 <div class="codewrapper sourceCode" id="cb33">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb33-1"><a href="#cb33-1" tabindex="-1"></a><span class="ex">$</span> bash do-stats.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt <span class="kw">|</span> <span class="fu">wc</span> <span class="at">-l</span></span></code></pre>
 </div>
 <p>so that the output is just the number of files processed rather than
 the names of the files that were processed.</p>
@@ -5275,12 +5275,12 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
-<span id="cb34-2"><a href="#cb34-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
-<span id="cb34-3"><a href="#cb34-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb34-4"><a href="#cb34-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
-<span id="cb34-5"><a href="#cb34-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb34-6"><a href="#cb34-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="co"># Calculate stats for Site A and Site B data files.</span></span>
+<span id="cb34-2"><a href="#cb34-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span>
+<span id="cb34-3"><a href="#cb34-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb34-4"><a href="#cb34-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datafile</span></span>
+<span id="cb34-5"><a href="#cb34-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb34-6"><a href="#cb34-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>The advantage is that this always selects the right files: she
 doesn’t have to remember to exclude the ‘Z’ files. The disadvantage is
@@ -5305,15 +5305,15 @@ <h3 class="callout-title">Variables in Shell Scripts<a class="anchor" aria-label
 <div class="codewrapper sourceCode" id="cb35">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" aria-hidden="true" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
-<span id="cb35-2"><a href="#cb35-2" aria-hidden="true" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb35-1"><a href="#cb35-1" tabindex="-1"></a><span class="fu">head</span> <span class="at">-n</span> <span class="va">$2</span> <span class="va">$1</span></span>
+<span id="cb35-2"><a href="#cb35-2" tabindex="-1"></a><span class="fu">tail</span> <span class="at">-n</span> <span class="va">$3</span> <span class="va">$1</span></span></code></pre>
 </div>
 <p>While you are in the <code>alkanes</code> directory, you type the
 following command:</p>
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> bash script.sh <span class="st">'*.pdb'</span> 1 1</span></code></pre>
 </div>
 <p>Which of the following outputs would you expect to see?</p>
 <ol style="list-style-type: decimal">
@@ -5334,7 +5334,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The correct answer is 2.</p>
 <p>The special variables <code>$1</code>, <code>$2</code> and
@@ -5343,8 +5343,8 @@ <h4 class="accordion-header" id="headingSolution3">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb37">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
-<span id="cb37-2"><a href="#cb37-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb37-1"><a href="#cb37-1" tabindex="-1"></a><span class="ex">$</span> head <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span>
+<span id="cb37-2"><a href="#cb37-2" tabindex="-1"></a><span class="ex">$</span> tail <span class="at">-n</span> 1 cubane.pdb ethane.pdb octane.pdb pentane.pdb propane.pdb</span></code></pre>
 </div>
 <p>The shell does not expand <code>'*.pdb'</code> because it is enclosed
 by quote marks. As such, the first argument to the script is
@@ -5370,7 +5370,7 @@ <h3 class="callout-title">Find the Longest File With a Given
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/alkanes pdb</span></code></pre>
 </div>
 <p>would print the name of the <code>.pdb</code> file in
 <code>shell-lesson-data/exercise-data/alkanes</code> that has the most
@@ -5379,7 +5379,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb39">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb39-1"><a href="#cb39-1" tabindex="-1"></a><span class="ex">$</span> bash longest.sh shell-lesson-data/exercise-data/writing txt</span></code></pre>
 </div>
 </div>
 </div>
@@ -5389,18 +5389,18 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
-<span id="cb40-2"><a href="#cb40-2" aria-hidden="true" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
-<span id="cb40-3"><a href="#cb40-3" aria-hidden="true" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
-<span id="cb40-4"><a href="#cb40-4" aria-hidden="true" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
-<span id="cb40-5"><a href="#cb40-5" aria-hidden="true" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
-<span id="cb40-6"><a href="#cb40-6" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb40-7"><a href="#cb40-7" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="co"># Shell script which takes two arguments:</span></span>
+<span id="cb40-2"><a href="#cb40-2" tabindex="-1"></a><span class="co">#    1. a directory name</span></span>
+<span id="cb40-3"><a href="#cb40-3" tabindex="-1"></a><span class="co">#    2. a file extension</span></span>
+<span id="cb40-4"><a href="#cb40-4" tabindex="-1"></a><span class="co"># and prints the name of the file in that directory</span></span>
+<span id="cb40-5"><a href="#cb40-5" tabindex="-1"></a><span class="co"># with the most lines which matches the file extension.</span></span>
+<span id="cb40-6"><a href="#cb40-6" tabindex="-1"></a></span>
+<span id="cb40-7"><a href="#cb40-7" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$1</span>/<span class="pp">*</span>.<span class="va">$2</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span> <span class="kw">|</span> <span class="fu">tail</span> <span class="at">-n</span> 2 <span class="kw">|</span> <span class="fu">head</span> <span class="at">-n</span> 1</span></code></pre>
 </div>
 <p>The first part of the pipeline, <code>wc -l $1/*.$2 | sort -n</code>,
 counts the lines in each file and sorts them numerically (largest last).
@@ -5433,23 +5433,23 @@ <h3 class="callout-title">Script Reading Comprehension<a class="anchor" aria-lab
 <div class="codewrapper sourceCode" id="cb41">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 1</span></span>
-<span id="cb41-2"><a href="#cb41-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb41-1"><a href="#cb41-1" tabindex="-1"></a><span class="co"># Script 1</span></span>
+<span id="cb41-2"><a href="#cb41-2" tabindex="-1"></a><span class="bu">echo</span> <span class="pp">*</span>.<span class="pp">*</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 2</span></span>
-<span id="cb42-2"><a href="#cb42-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
-<span id="cb42-3"><a href="#cb42-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb42-4"><a href="#cb42-4" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
-<span id="cb42-5"><a href="#cb42-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="co"># Script 2</span></span>
+<span id="cb42-2"><a href="#cb42-2" tabindex="-1"></a><span class="cf">for</span> filename <span class="kw">in</span> <span class="va">$1</span> <span class="va">$2</span> <span class="va">$3</span></span>
+<span id="cb42-3"><a href="#cb42-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb42-4"><a href="#cb42-4" tabindex="-1"></a>    <span class="fu">cat</span> <span class="va">$filename</span></span>
+<span id="cb42-5"><a href="#cb42-5" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Script 3</span></span>
-<span id="cb43-2"><a href="#cb43-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="co"># Script 3</span></span>
+<span id="cb43-2"><a href="#cb43-2" tabindex="-1"></a><span class="bu">echo</span> <span class="va">$@</span>.pdb</span></code></pre>
 </div>
 </div>
 </div>
@@ -5459,7 +5459,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solutions</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>In each case, the shell expands the wildcard in <code>*.pdb</code>
 before passing the resulting list of file names as arguments to the
@@ -5497,26 +5497,26 @@ <h3 class="callout-title">Debugging Scripts<a class="anchor" aria-label="anchor"
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
-<span id="cb45-2"><a href="#cb45-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
-<span id="cb45-3"><a href="#cb45-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
-<span id="cb45-4"><a href="#cb45-4" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
-<span id="cb45-5"><a href="#cb45-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
-<span id="cb45-6"><a href="#cb45-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="co"># Calculate stats for data files.</span></span>
+<span id="cb45-2"><a href="#cb45-2" tabindex="-1"></a><span class="cf">for</span> datafile <span class="kw">in</span> <span class="st">"</span><span class="va">$@</span><span class="st">"</span></span>
+<span id="cb45-3"><a href="#cb45-3" tabindex="-1"></a><span class="cf">do</span></span>
+<span id="cb45-4"><a href="#cb45-4" tabindex="-1"></a>    <span class="bu">echo</span> <span class="va">$datfile</span></span>
+<span id="cb45-5"><a href="#cb45-5" tabindex="-1"></a>    <span class="fu">bash</span> goostats.sh <span class="va">$datafile</span> stats-<span class="va">$datafile</span></span>
+<span id="cb45-6"><a href="#cb45-6" tabindex="-1"></a><span class="cf">done</span></span></code></pre>
 </div>
 <p>When you run it from the <code>north-pacific-gyre</code>
 directory:</p>
 <div class="codewrapper sourceCode" id="cb46">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb46-1"><a href="#cb46-1" tabindex="-1"></a><span class="ex">$</span> bash do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>the output is blank. To figure out why, re-run the script using the
 <code>-x</code> option:</p>
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> bash <span class="at">-x</span> do-errors.sh NENE<span class="pp">*</span>A.txt NENE<span class="pp">*</span>B.txt</span></code></pre>
 </div>
 <p>What is the output showing you? Which line is responsible for the
 error?</p>
@@ -5528,7 +5528,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Show me the solution</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>The <code>-x</code> option causes <code>bash</code> to run in debug
 mode. This prints out each command as it is run, which will help you to
@@ -5626,9 +5626,9 @@ <h3 class="card-title">Objectives</h3>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
-<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop/shell-lesson-data/exercise-data/writing</span>
+<span id="cb1-3"><a href="#cb1-3" tabindex="-1"></a><span class="ex">$</span> cat haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5649,7 +5649,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> grep not haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5672,7 +5672,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb5">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" tabindex="-1"></a><span class="ex">$</span> grep The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5691,7 +5691,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb7">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> The haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5705,7 +5705,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb9">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb9-1"><a href="#cb9-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-w</span> <span class="st">"is not"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5722,7 +5722,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb11">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="st">"it"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5740,7 +5740,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb13">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb13-1"><a href="#cb13-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5753,7 +5753,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb15">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb15-1"><a href="#cb15-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-i</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5768,7 +5768,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb17">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb17-1"><a href="#cb17-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-n</span> <span class="at">-w</span> <span class="at">-v</span> <span class="st">"the"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5791,7 +5791,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb19">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb19-1"><a href="#cb19-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-r</span> Yesterday .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5806,7 +5806,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb21">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb21-1"><a href="#cb21-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">--help</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5859,7 +5859,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The correct answer is 3, because the <code>-w</code> option looks
 only for whole-word matches. The other options will also match ‘of’ when
@@ -5868,12 +5868,12 @@ <h4 class="accordion-header" id="headingSolution1">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="wildcards" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="wildcards" class="callout-inner">
-<h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="wildcards">Wildcards<a class="anchor" aria-label="anchor" href="#wildcards"></a>
 </h3>
 <div class="callout-content">
 <p><code>grep</code>‘s real power doesn’t come from its options, though;
@@ -5887,7 +5887,7 @@ <h3 class="callout-title">Wildcards<a class="anchor" aria-label="anchor" href="#
 <div class="codewrapper sourceCode" id="cb24">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb24-1"><a href="#cb24-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="at">-E</span> <span class="st">"^.o"</span> haiku.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5938,13 +5938,13 @@ <h3 class="callout-title">Tracking a Species<a class="anchor" aria-label="anchor
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
-<span id="cb28-2"><a href="#cb28-2" aria-hidden="true" tabindex="-1"></a><span class="op">&gt;</span></span>
-<span id="cb28-3"><a href="#cb28-3" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-4"><a href="#cb28-4" aria-hidden="true" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
-<span id="cb28-5"><a href="#cb28-5" aria-hidden="true" tabindex="-1"></a><span class="kw">|</span></span>
-<span id="cb28-6"><a href="#cb28-6" aria-hidden="true" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
-<span id="cb28-7"><a href="#cb28-7" aria-hidden="true" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb28-1"><a href="#cb28-1" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> : <span class="at">-f</span> 2</span>
+<span id="cb28-2"><a href="#cb28-2" tabindex="-1"></a><span class="op">&gt;</span></span>
+<span id="cb28-3"><a href="#cb28-3" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-4"><a href="#cb28-4" tabindex="-1"></a><span class="fu">grep</span> <span class="at">-w</span> <span class="va">$1</span> <span class="at">-r</span> <span class="va">$2</span></span>
+<span id="cb28-5"><a href="#cb28-5" tabindex="-1"></a><span class="kw">|</span></span>
+<span id="cb28-6"><a href="#cb28-6" tabindex="-1"></a><span class="va">$1</span><span class="ex">.txt</span></span>
+<span id="cb28-7"><a href="#cb28-7" tabindex="-1"></a><span class="fu">cut</span> <span class="at">-d</span> , <span class="at">-f</span> 1,3</span></code></pre>
 </div>
 <p>Hint: use <code>man grep</code> to look for how to grep text
 recursively in a directory and <code>man cut</code> to select more than
@@ -5959,7 +5959,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <pre class="source"><code>grep -w $1 -r $2 | cut -d : -f 2 | cut -d , -f 1,3 &gt; $1.txt</code></pre>
 <p>Actually, you can swap the order of the two cut commands and it still
@@ -5970,7 +5970,7 @@ <h4 class="accordion-header" id="headingSolution2">Show me the solution</h4>
 <div class="codewrapper sourceCode" id="cb30">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb30-1"><a href="#cb30-1" tabindex="-1"></a><span class="ex">$</span> bash count-species.sh bear .</span></code></pre>
 </div>
 </div>
 </div>
@@ -6007,7 +6007,7 @@ <h3 class="callout-title">Little Women<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solutions</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <pre class="source"><code>for sis in Jo Meg Beth Amy
 do
@@ -6070,7 +6070,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb34-1"><a href="#cb34-1" tabindex="-1"></a><span class="ex">$</span> find .</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6106,7 +6106,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb36">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb36-1"><a href="#cb36-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> d</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6123,7 +6123,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb38">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb38-1"><a href="#cb38-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-type</span> f</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6146,7 +6146,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb40">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb40-1"><a href="#cb40-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="pp">*</span>.txt</span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6161,7 +6161,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb42">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb42-1"><a href="#cb42-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> numbers.txt</span></code></pre>
 </div>
 <p><code>find</code> did what we asked; we just asked for the wrong
 thing.</p>
@@ -6173,7 +6173,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb43">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb43-1"><a href="#cb43-1" tabindex="-1"></a><span class="ex">$</span> find . <span class="at">-name</span> <span class="st">"*.txt"</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6182,12 +6182,12 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <span><span class="va">.</span><span class="op">/</span><span class="va">writing</span><span class="op">/</span><span class="va">haiku.txt</span></span>
 <span><span class="va">.</span><span class="op">/</span><span class="va">numbers.txt</span></span></code></pre>
 </div>
-<div id="listing-vs.-finding" class="callout callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="listing-vs.-finding" class="callout-inner">
-<h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs.-finding"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="listing-vs--finding">Listing vs. Finding<a class="anchor" aria-label="anchor" href="#listing-vs--finding"></a>
 </h3>
 <div class="callout-content">
 <p><code>ls</code> and <code>find</code> can be made to do similar
@@ -6207,7 +6207,7 @@ <h3 class="callout-title">Listing vs. Finding<a class="anchor" aria-label="anch
 <div class="codewrapper sourceCode" id="cb45">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb45-1"><a href="#cb45-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6227,7 +6227,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <div class="codewrapper sourceCode" id="cb47">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb47-1"><a href="#cb47-1" tabindex="-1"></a><span class="ex">$</span> wc <span class="at">-l</span> ./writing/LittleWomen.txt ./writing/haiku.txt ./numbers.txt</span></code></pre>
 </div>
 <p>which is what we wanted. This expansion is exactly what the shell
 does when it expands wildcards like <code>*</code> and <code>?</code>,
@@ -6241,7 +6241,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb48">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb48-1"><a href="#cb48-1" tabindex="-1"></a><span class="ex">$</span> grep <span class="st">"searching"</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.txt"</span><span class="va">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6277,7 +6277,7 @@ <h3 class="callout-title">Matching and Subtracting<a class="anchor" aria-label="
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>Option 1 is correct. Putting the match expression in quotes prevents
 the shell expanding it, so it gets passed to the <code>find</code>
@@ -6293,12 +6293,12 @@ <h4 class="accordion-header" id="headingSolution4">Show me the solution</h4>
 </div>
 </div>
 </div>
-<div id="binary-files" class="callout callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="binary-files" class="callout-inner">
-<h3 class="callout-title">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="binary-files">Binary Files<a class="anchor" aria-label="anchor" href="#binary-files"></a>
 </h3>
 <div class="callout-content">
 <p>We have focused exclusively on finding patterns in text files. What
@@ -6344,7 +6344,7 @@ <h3 class="callout-title">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" aria-hidden="true" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb50-1"><a href="#cb50-1" tabindex="-1"></a><span class="fu">wc</span> <span class="at">-l</span> <span class="va">$(</span><span class="fu">find</span> . <span class="at">-name</span> <span class="st">"*.dat"</span><span class="va">)</span> <span class="kw">|</span> <span class="fu">sort</span> <span class="at">-n</span></span></code></pre>
 </div>
 </div>
 </div>
@@ -6354,7 +6354,7 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Show me the solution</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p>Find all files with a <code>.dat</code> extension recursively
@@ -6440,8 +6440,8 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://swcarpentry.github.io/shell-novice/instructor/aio.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/aio.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/discuss.html b/instructor/discuss.html
index 1aa95fadc..95c912217 100644
--- a/instructor/discuss.html
+++ b/instructor/discuss.html
@@ -391,7 +391,7 @@ <h1>Discussion</h1>
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/discuss.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/images.html b/instructor/images.html
index 286ad98a7..37ab1ec29 100644
--- a/instructor/images.html
+++ b/instructor/images.html
@@ -392,8 +392,8 @@ <h3 id="05-loop-figure-1">Figure 1</h3>
   "url": "https://swcarpentry.github.io/shell-novice/instructor/images.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/images.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/index.html b/instructor/index.html
index 9091046ae..0a5eacfd6 100644
--- a/instructor/index.html
+++ b/instructor/index.html
@@ -385,14 +385,13 @@ <h3 class="callout-title">Prerequisites<a class="anchor" aria-label="anchor" hre
 folder as your working directory.</li>
 </ol><p>In the lesson, you will find out how to access the data files in this
 folder.</p>
-<div id="where-to-type-commands-how-to-open-a-new-shell" class="callout callout">
+<div id="callout1" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
-<div id="where-to-type-commands-how-to-open-a-new-shell" class="callout-inner">
-<h3 class="callout-title">Where to type commands: How to open a new
-shell<a class="anchor" aria-label="anchor" href="#where-to-type-commands-how-to-open-a-new-shell"></a>
-</h3>
+<div class="section level3 callout-title callout-inner">
+<h3 class="callout-title" id="where-to-type-commands-how-to-open-a-new-shell">Where to type commands: How to open a new
+shell<a class="anchor" aria-label="anchor" href="#where-to-type-commands-how-to-open-a-new-shell"></a></h3>
 <div class="callout-content">
 <p>The shell is a program that enables us to send commands to the
 computer and receive output. It is also referred to as the terminal or
@@ -525,8 +524,8 @@ <h4 class="accordion-header" id="headingSolution3">Linux</h4>
   "url": "https://swcarpentry.github.io/shell-novice/instructor/index.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/index.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/instructor-notes.html b/instructor/instructor-notes.html
index aa12d32fe..ab9affdfe 100644
--- a/instructor/instructor-notes.html
+++ b/instructor/instructor-notes.html
@@ -490,7 +490,7 @@ <h1>Instructor Notes</h1>
 <div class="codewrapper sourceCode" id="cb1">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="va">PS1</span><span class="op">=</span><span class="st">'$ '</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a><span class="va">PS1</span><span class="op">=</span><span class="st">'$ '</span></span></code></pre>
 </div>
 </li>
 <li><p>On Windows machines if <code>nano</code> hasn’t been properly
@@ -505,8 +505,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb2">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd</span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" tabindex="-1"></a><span class="ex">$</span> cd</span>
+<span id="cb2-2"><a href="#cb2-2" tabindex="-1"></a><span class="ex">$</span> cd Desktop</span></code></pre>
 </div>
 <p>will always put someone on their desktop (unless their machine is
 backed up using enterprise OneDrive, see next point). Have them create
@@ -523,8 +523,8 @@ <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i
 <div class="codewrapper sourceCode" id="cb3">
 <h3 class="code-label">BASH<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"~/OneDrive - Name Of Enterprise/Desktop"</span></span>
-<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"C:/Users/Username/OneDrive - Name Of Enterprise/Desktop"</span></span></code></pre>
+<pre class="sourceCode bash" tabindex="0"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"~/OneDrive - Name Of Enterprise/Desktop"</span></span>
+<span id="cb3-2"><a href="#cb3-2" tabindex="-1"></a><span class="ex">$</span> cd <span class="st">"C:/Users/Username/OneDrive - Name Of Enterprise/Desktop"</span></span></code></pre>
 </div>
 <p>One way to spot if the computer is using this kind of configuration
 is to look at files, folders or links on the desktop. Usually the icon
@@ -652,8 +652,8 @@ <h3 id="03-create-headingInstructor1">
   "url": "https://swcarpentry.github.io/shell-novice/instructor/instructor-notes.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/instructor-notes.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/key-points.html b/instructor/key-points.html
index 83ee6d155..cb2b6169d 100644
--- a/instructor/key-points.html
+++ b/instructor/key-points.html
@@ -512,8 +512,8 @@ <h2 class="accordion-header" id="flush-headingTwelve">
   "url": "https://swcarpentry.github.io/shell-novice/instructor/key-points.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/key-points.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/profiles.html b/instructor/profiles.html
index f6a11eca4..bc2a82ef7 100644
--- a/instructor/profiles.html
+++ b/instructor/profiles.html
@@ -288,8 +288,8 @@ <h1>Learner Profiles</h1>
   "url": "https://swcarpentry.github.io/shell-novice/instructor/profiles.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/profiles.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/instructor/reference.html b/instructor/reference.html
index 23644060c..a4f0aea22 100644
--- a/instructor/reference.html
+++ b/instructor/reference.html
@@ -634,7 +634,7 @@ <h3 id="miscellaneous">Miscellaneous<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/instructor/reference.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/key-points.html b/key-points.html
index f3dd8758f..90df882f0 100644
--- a/key-points.html
+++ b/key-points.html
@@ -510,8 +510,8 @@ <h2 class="accordion-header" id="flush-headingTwelve">
   "url": "https://swcarpentry.github.io/shell-novice/key-points.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/key-points.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/md5sum.txt b/md5sum.txt
index 7e71ac86b..dee4a0587 100644
--- a/md5sum.txt
+++ b/md5sum.txt
@@ -15,4 +15,4 @@
 "learners/reference.md" "a1ed44386dc6c24af7d281a697f08cb6" "site/built/reference.md" "2024-02-20"
 "learners/setup.md" "163fdeac34851abe2b54b60e4b4a74c8" "site/built/setup.md" "2024-02-20"
 "profiles/learner-profiles.md" "5fe5bf7537072422b91ed393ada03f9a" "site/built/learner-profiles.md" "2024-02-20"
-"renv/profiles/lesson-requirements/renv.lock" NA "site/built/renv.lock" "2024-02-27"
+"renv/profiles/lesson-requirements/renv.lock" NA "site/built/renv.lock" "2024-03-05"
diff --git a/pkgdown.yml b/pkgdown.yml
index 49b8bc5a4..e2128c7b9 100644
--- a/pkgdown.yml
+++ b/pkgdown.yml
@@ -1,6 +1,6 @@
-pandoc: 2.19.2
+pandoc: 3.1.11
 pkgdown: 2.0.7
 pkgdown_sha: ~
 articles: {}
-last_built: 2024-02-27T00:43Z
+last_built: 2024-03-05T00:42Z
 
diff --git a/profiles.html b/profiles.html
index 228fdac4f..b71443472 100644
--- a/profiles.html
+++ b/profiles.html
@@ -288,8 +288,8 @@ <h1>Learner Profiles</h1>
   "url": "https://swcarpentry.github.io/shell-novice/profiles.html",
   "identifier": "https://swcarpentry.github.io/shell-novice/profiles.html",
   "dateCreated": "2014-10-22",
-  "dateModified": "2024-02-27",
-  "datePublished": "2024-02-27"
+  "dateModified": "2024-03-05",
+  "datePublished": "2024-03-05"
 }
 
   </script><script>
diff --git a/reference.html b/reference.html
index 069a78283..dbddcfb2c 100644
--- a/reference.html
+++ b/reference.html
@@ -632,7 +632,7 @@ <h3 id="miscellaneous">Miscellaneous<a class="anchor" aria-label="anchor" href="
   "identifier": "https://swcarpentry.github.io/shell-novice/reference.html",
   "dateCreated": "2014-10-22",
   "dateModified": "2024-02-20",
-  "datePublished": "2024-02-27"
+  "datePublished": "2024-03-05"
 }
 
   </script><script>