There have always been good resources for JavaScript online. But recently there’s been some robust libraries created and made available that do everything from animation to AJAX. These libraries are ways for novice developers to quickly implement complex JavaScript functionality into sites while adhering to good programming rules.

One problem with some of these libraries, if used in their entirety, is the file size they can add to a web page. Often it is best to just incorporate the code that does what you need and delete the rest – if you know how to do that. Here are a few of the most popular.

Script.aculo.us   

“script.aculo.us provides you with easy-to-use, compatible and, ultimately, totally cool JavaScript libraries to make your web sites and web applications fly, Web 2.0 style.”

jQuery  

“jQuery is a new type of Javascript library. It is not a huge, bloated, framework promising the best in AJAX - nor is just a set of needlessly complex enhancements - jQuery is designed to change the way that you write Javascript.”

Yahoo! User Interface Library 

“The Yahoo! User Interface (YUI) Library is a set of utilities and controls, written in JavaScript, for building richly interactive web applications using techniques such as DOM scripting, DHTML and AJAX. The YUI Library also includes several core CSS resources.”