Add multimedia instructions to index page

index.md

@@ -18,3 +18,13 @@ All pages will appear in the menu to the left. For example, the page with an ord
 ## Markdown
 
 All pages are written in Markdown. See [Basic Syntax](https://www.markdownguide.org/basic-syntax/)
+
+## Multimedia
+
+To add images to a page, add them to the /assets/img folder. Use the complete path in the image source, including the repository. Example:
+
+    ![Artistic rendering of computers\](/systems-librarianship/assets/img/binary-monitor-particles-600px.jpg)
+
+To embed YouTube videos, use the iframe embed code. Example:
+
+    <iframe width="560" height="315" src="https://www.youtube.com/embed/08VDn3vdD4A?si=EBxc050TnfEXUjAV" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen\></iframe>