Template Tags, Themes and PHP Basics
Turn your WordPress Theme into a finely tuned machine. This concise breakdown of the most important pieces of your WordPress Theme will keep your coding efforts focused and productive. Even the experienced WP site developer will appreciate how these slides serve as a great reminder of the theming basics.
These slides are courtesy of Jeremy Clarke’s presentation at WordCamp: Intro to WordPress Theming.
You can find other great WordPress tutorials and presentations at WordPress.tv.
P.S. What I really like is the example showing all of the creative uses of custom sidebars (slide 30 & at 42 min. in the video):
And the code showing how to add new custom sidebars to your theme (slide 31):