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YDN YUI

YUI Library

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 frontend engineers at Yahoo! and contributors from around the world, it's an industrial-strength JavaScript library for professionals who love JavaScript.

Get Started with YUI 2 or YUI 3

Follow the YUI Project

YUI 2 — robust and proven

Launched February 2006
Used on thousands of sites around the Web — including Yahoo!
One of the most popular, best-documented JavaScript/CSS libraries available
Comprehensive suite of utilities and widgets

Get Started with YUI 2

YUI 3 — YUI evolved

Launched September 2009
YUI's next-generation framework — used on the new Yahoo! home page
Rebuilt from the ground up to be incredibly fast, powerful, and secure
Full suite of utilities; widgets coming in 2010
Gallery of community-contributed components

Get Started with YUI 3

Download, watch, or fork any of the open-source YUI projects on GitHub.

Keep up with YUI's developers and the YUI community on YUI Blog.

On Twitter, follow YUILibrary to hear about all the latest news and upcoming events related to the YUI project.

Join YUILibrary.com to participate in the YUI Forums, contribute to the YUI 3 Gallery and to file bug reports and feature requests on any YUI project.