Examples Module

An example, like a picture, is worth 1000 words. Until recently Drupal programming examples existed but were spread among documentation pages, blog posts, and the Drupal CVS repository; some searching required. That changed in late 2009 with the introduction of the Examples for Developers module. Its purpose: "to provide high-quality, well-documented API examples for a broad range of Drupal core functionality". Now you can find high-quality, working Drupal 6 and 7 code examples in one place, many with SimpleTests.