jQuery is a fast and concise JavaScript Library that simplifies HTML document traversing, event handling, animating, and Ajax interactions for rapid web development. jQuery is designed to change the way that you write JavaScript.

What's New

Elements are now returned in document order.
.live() can now prevent bubbling.
:visible/:hidden are now significantly faster.
As are all the width/height methods.
Selectors are much faster in Internet Explorer.
appendTo/etc. have had a slight API tweak.
Full details can be found in the 1.3.2 Release Notes. More...

Prototype is a JavaScript Framework that aims to ease development of dynamic web applications.

Featuring a unique, easy-to-use toolkit for class-driven development and the nicest Ajax library around, Prototype is quickly becoming the codebase of choice for web application developers everywhere.

What's New

Yesterday we released Prototype 1.6.0.3, the result of some much-needed bug fixes, and a stopgap release on the road to 1.6.1.

It's a backwards-compatible, drop-in replacement recommended for all users of Prototype 1.6. We've fixed 30 bugs and made 25 other improvements to our already-rock-solid library. More...

YUI is a library of JavaScript utilities and controls for building richly interactive web applications using techniques such as DOM Scripting, DHTML, and Ajax. It is available under a BSD license and is free for all uses.

What's New

Version 2.7.0 introduces a new StyleSheet component, graduates three components out of beta, improves support for the upcoming release of IE8, includes over 180 bug fixes and enhancements, and ships with more than 300 functional examples. More...

Dojo is an Open Source DHTML toolkit written in JavaScript. Dojo aims to solve some long-standing historical problems with DHTML which prevented mass adoption of dynamic web application development.

What's New

This release is monumental. Though the release notes only cover the additions and possible changes from 1.2, the overall implications of the fixed issues and new functionality are staggering. The focus of 1.3 was Internet Explorer 8 and WebKit (Chrome, Safari) compatibility and general performance, though the overall scope of Dojo invariably states a slew of new widgets, functions and API cleanups have landed, and are available now on two quality content distribution networks out of the box. More...

MooTools is a compact, modular, Object-Oriented JavaScript framework designed for the intermediate to advanced JavaScript developer. It allows you to write powerful, flexible, and cross-browser code with its elegant, well documented, and coherent API.

MooTools code respects strict standards and doesn't throw any warnings. It's extensively documented and has meaningful variable names: a joy to browse and a snap to understand.

What's New

MooTools 1.2.2 is a mainly a bug fix release but it also includes an almost entirely new Class.js. The reasoning behind this is that the old Class.js didnÕt play nicely with some advanced usages of this.parent() present in the new MooTools-More. We already had the script ready and tested in the MooTools 2.0 branch so we simply ÒbackportedÓ it to 1.2.2. Other than providing the parent fixes, the new Class also features a much more robust inheritance model, especially when dealing with objects. More...

qooxdoo is a comprehensive and innovative Ajax application framework. Leveraging object-oriented JavaScript allows developers to build impressive cross-browser applications. No HTML, CSS nor DOM knowledge is needed. It includes a platform-independent development tool chain, a state-of-the-art GUI toolkit and an advanced client-server communication layer. It is open source under an LGPL/EPL dual license.

What's New

As planned the Open Source RIA Framework qooxdoo is available in a new release 0.8.2. It is quite a comprehensive maintenance release, with many improvements and bugfixes over the previous version. More...

script.aculo.us provides you with easy-to-use, cross-browser user interface JavaScript libraries to make your web sites and web applications fly.

What's New

Script.aculo.us 1.8.2 is an update recommended for all users. More...

jQuery UI provides abstractions for low-level interaction and animation, advanced effects and high-level, themeable widgets, built on top of the jQuery JavaScript Library, that you can use to build highly interactive web applications.

What's New

The first maintenance release for jQuery UI 1.7 More...

With Scripteka you can view an extensive library of Prototype and Script.aculo.us based extensions/plugins, rate and use rating to find the coolest scripts out there, submit your own creations and get community feedback, and subscribe to the newest additions to the library.

Screw.Unit is a Behavior-Driven Testing Framework for Javascript. It features nested describes. Its goals are to provide: a DSL for elegant, readable, organized specs; an interactive runner that can execute focused specs and describes; and brief, extensible source-code.

Jasmine is yet another JavaScript testing framework. It's heavily influenced by JSSpec, ScrewUnit & JSpec, which are all influenced by RSpec. But each of those was lacking in some way: JSSpec & ScrewUnit require a DOM. JSpec's DOM-less assumption was a great start, but it needed asynchronous support.

So we started over. And TDD'd a whole new framework. Enjoy.

JsUnit is a Unit Testing framework for client-side (in-browser) JavaScript. It is essentially a port of JUnit to JavaScript. Also included is a platform for automating the execution of tests on multiple browsers and mutiple machines running different OSs. Its development began in January 2001.

JJ is a mock framework for JavaScript in the spirit of RR.

JSMock is a fully featured Mock Object library for JavaScript that provides the necessary tools to do effective interactive based testing. JSMock provides expectation recording and matching, and has the ability to return, throw, and stub on object method calls. The interface is simple and easy to use, which makes testing easy.

amok (pronounced 'amok' not 'A Mok') is a user friendly mocking framework named after the signature dish of Cambodia.

What's New

Added support for mocking all instances of a class

Mock4JS is a dynamic-mock library for Javascript. It enables developers to write tests that exercise and verify the interactions between the objects in the application. Its syntax is very expressive and is closely based on jMock 1.

There are a couple of mock frameworks for JavaScript but none really did what I needed. So I took my testing problems, some inspiration from mockito and a few days off to write MockMe.

What's New

After a discussion with one of the Mockito guys at Agile 2008, I changed the stubbing syntax. More...

The YUI Compressor is a JavaScript minifier designed to be 100% safe and yield a higher compression ratio than most other tools. Tests on the YUI Library have shown savings of over 20% compared to JSMin (becoming 10% after HTTP compression). Starting with version 2.0, the YUI Compressor is also able to compress CSS files by using a port of Isaac Schlueter's regular-expression-based CSS minifier.