This screencasts shows some aspects of theming forms, using the hook_form_FORM_ID_alter functions. Only a few properties of the form elements are discussed in the screencast, including:

This screencast discusses render arrays in a semi-structured way. Here is some kind of summary:

This screencast shows an example of the special case of theming Views. This does, in general, work as theming other parts of Drupal – you copy template files to you theme and modify them, you write preprocess functions, and you write theme functions.

This screencast shows that theme functions and template files are actually interchangable from a theme layer point of view. That means that it doesn't matter if you have a template file called field--body--page.tpl.php, or a theme function called MYTHEME_field__body__page.

This screencast shows that while some elements on a Drupal page are themed by template files, quite a few are themed by *theme functions*. In this screencast you will learn:

This screencast shows some more useful things with preprocess functions:

This screencast introduces the concept of preprocess functions – functions usually used for adding new variables to your template files. By using preprocess functions you can move complex logic out of the template files, and feed the templates with pre-made variables instead.

This screencast shows how you can use template files to customize the markup on your site. In more detail, it shows:

The secret of using Drupal effeciently is often to make sure that you have to do as little as possible. Unfortunately this means that you sometimes should change some old habits, and do things in a way that at first glance does not seem to be the quickest and easiest. Why?