API reference
By Admin - Posted on January 11th, 2008
Drupal developer's documentation. Newcomers to Drupal development should read the conceptual information provided in the "Components of Drupal" section, and then proceed to examine one of the heavily-documented example modules below. The examples are fully-functioning Drupal modules, so you can download them from the contributions repository and alter them as you experiment.
Website:
http://api.drupal.org/