<!--?xml version="1.0" encoding="UTF-8"?-->
The YUI Library is a set of utilities and controls, written with JavaScript and CSS, for building richly interactive web applications using techniques such as DOM scripting, DHTML and AJAX. YUI is available under a BSD license and is free for all uses.
YUI is proven, scalable, fast, and robust. Built by front end engineers at Yahoo! and contributors from around the world, it's an industrial-strength JavaScript library for professionals who love JavaScript.
The project maintained by Yahoo Developer Network and the source can be downloaded form Git-hub.
Project URL
http://developer.yahoo.com/yui/
Below is the list of various modules that YUI library offers.