Reorganize/condense intro

episodes/01-intro.md

@@ -17,7 +17,7 @@ exercises: 0
 
 ::::::::::::::::::::::::::::::::::::::::::::::::::
 
-### Background
+### What is the Shell?
 
 Humans and computers commonly interact in many different ways, such as through a keyboard and mouse,
 touch screen interfaces, or using speech recognition systems.
@@ -26,52 +26,39 @@ The most widely used way to interact with personal computers is called a
 With a GUI, we give instructions by clicking a mouse and using menu-driven interactions.
 
 While the visual aid of a GUI makes it intuitive to learn,
-this way of delivering instructions to a computer scales very poorly.
+this way of interacting scales very poorly for some tasks.
+
+A **command-line interface** (CLI) allows users to to interact with computer by reading
+and writing text. It excels at making repetitive tasks automatic and fast.
+
+A **shell** is a particular program that lets you type commands.
+In this workshop, we will be using "Bash" which is the most popular Unix shell.
+Bash is often the default shell on Unix and in Unix-like tools for Windows.
+
+### Why use the shell?
+
 Imagine the following task:
 for a literature search, you have to copy the third line of one thousand text files in one thousand
 different directories and paste it into a single file.
+
 Using a GUI, you would not only be clicking at your desk for several hours,
 but you could potentially also commit an error in the process of completing this repetitive task.
-This is where we take advantage of the Unix shell.
-The Unix shell is both a **command-line interface** (CLI) and a scripting language,
-allowing such repetitive tasks to be done automatically and fast.
-With the proper commands, the shell can repeat tasks with or without some modification
-as many times as we want.
-Using the shell, the task in the literature example can be accomplished in seconds.
-
-### The Shell
-
-The shell is a program where users can type commands.
-With the shell, it's possible to invoke complicated programs like climate modeling software
-or simple commands that create an empty directory with only one line of code.
-The most popular Unix shell is Bash (the Bourne Again SHell ---
-so-called because it's derived from a shell written by Stephen Bourne).
-Bash is the default shell on most modern implementations of Unix and in most packages that provide
-Unix-like tools for Windows.
-Note that 'Git Bash' is a piece of software that enables Windows users to use a Bash like interface
-when interacting with Git.
+
+Using a CLI, you can write a series of commands that does this consistently and nearly instantly.
+
+The shell can be used for simple tasks like creating an empty folder
+and for launching (even complex) programs with a single command.
+In fact, some tools and resources such as cloud computing systems
+usually require users to be familiar with the shell.
+Shell commands can be combined together and saved into reproducible *scripts*
+that handle large volumes of data automatically.
 
 Using the shell will take some effort and some time to learn.
-While a GUI presents you with choices to select, CLI choices are not automatically presented to you,
-so you must learn a few commands like new vocabulary in a language you're studying.
-However, unlike a spoken language, a small number of "words" (i.e. commands) gets you a long way,
-and we'll cover those essential few today.
-
-The grammar of a shell allows you to combine existing tools into powerful
-pipelines and handle large volumes of data automatically. Sequences of
-commands can be written into a *script*, improving the reproducibility of
-workflows.
-
-In addition, the command line is often the easiest way to interact with remote machines
-and supercomputers.
-Familiarity with the shell is near essential to run a variety of specialized tools and resources
-including high-performance computing systems.
-As clusters and cloud computing systems become more popular for scientific data crunching,
-being able to interact with the shell is becoming a necessary skill.
-We can build on the command-line skills covered here
-to tackle a wide range of scientific questions and computational challenges.
-
-Let's get started.
+While a GUI presents you with choices to select, CLI choices are not automatically presented to you. It can be daunting at first, but once you've come familliar with this different style
+of iteracting, you will be able to find and use the information you need to accomplish
+a huge variety of tasks.
+
+### Let's get started.
 
 When the shell is first opened, you are presented with a **prompt**,
 indicating that the shell is waiting for input.