This document talks mainly about core, not contrib, and how it is OOD <br>but not OOP.&nbsp; With PHP5, one would expect more true OOP to make its <br>way into contrib, and perhaps to core (over time).<br><br><a href="http://api.drupal.org/api/file/oop.html/6">
Drupal Programming from an Object-Oriented Perspective</a><br><br><a href="http://api.drupal.org/api/file/developer/topics/oop.html/6">http://api.drupal.org/api/file/developer/topics/oop.html/6</a><br>