Start the demo / slideshow by running jQuery101.htm.

Clicking on most of the items in the lists will usually pop up the code to the right of the list, that explains the feature.

Clicking on most of the icons to the left of each list item will usually pop up a comment about the item, to the left of the list.

I also recommend exploring the actual source code.

The .docx file contains a copy of most of the comments embedded in the demo.