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YUI Library

YUI Library

YUI is a free, open source JavaScript and CSS framework for building richly interactive web applications. YUI is provided under a BSD license and is available on GitHub for forking and contribution.

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.

YUI 3 — Industrial Strength

  • Actively developed by the YUI team and worldwide contributors
  • Built to be incredibly fast, powerful, and secure
  • Yahoo! trusted, used by millions every day

YUI Gallery

Use the YUI Gallery to extend YUI with modules provided by our community and hosted by us.


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

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

Follow @YUILibrary on Twitter for short & timely project updates.

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

Also in the YUI Project

YUI Compressor

YUI Compressor is a tool written in Java that minifies your JavaScript and CSS.

YUI Test

YUI Test is a complete testing framework for JavaScript and Web applications. YUI Test integrates well with continuous integration systems.

Selleck & YUI Doc for Node.js

These pre-release and unofficial projects, created by YUI engineers, help us document the YUI project. Selleck is a Mustache-based documentation generator. YUI Doc for Node.js is an API documentation generator. Both are used on YUILibrary.com.

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