Introduction

Until a few years ago, mentioning the word JavaScript to a themer would usually result in groans about inconsistencies in browser support, lack of standards, difficulty in debugging, and a myriad of other complaints. Thankfully, however, things have changed considerably since then. Browsers have evolved and standards have improved. JavaScript is now a potent weapon in any themer's armory and this is especially true with the introduction of cross-browser libraries and frameworks which address most of the aforementioned issues with it.

JavaScript libraries take out the majority of the hassle involved in writing code which will be executed in a variety of browsers each with its own vagaries. Drupal, by default, uses jQuery, a lightweight, robust, and well-supported package which, since its introduction, has become one of the most popular libraries in use today. While it is possible to wax eloquent about its features and ease of use, its most appealing factor is that it is a whole...