Javascript libraries have become fundamental to good web design, almost all ste nowadays have some element of javascript or Ajax present. It is probably the main element in developing the Web 2.0 movement. There are many Javascript Frameworks.

1. script.aculo.us (homepage: http://www.script.aculo.us)

Note: script.aculo.us is not a Framework by its self but it is an addon for Prototype.
Description: script.aculo.us is a JavaScript library built on the Prototype JavaScript Framework, providing dynamic visual effects and user interface elements via the Document Object Model.

It is most notably included with Seaside and Ruby on Rails, but also provided separately to work with other web application frameworks and scripting languages.

script.aculo.us was extracted by Thomas Fuchs from his work on fluxiom, a web based digital asset management tool by the design company wollzelle. It was first released to the public in June 2005.

2. Prototype (homepage: http://www.prototypejs.org/)

Description: The Prototype JavaScript Framework is a JavaScript framework created by Sam Stephenson which provides an Ajax framework and other utilities. It is implemented as a single file of JavaScript code, usually named prototype.js. Prototype is distributed standalone, but also as part of larger projects, such as Ruby on Rails, script.aculo.us and Rico

3. Mootools (homepage: http://www.mootools.net/)

Description: MooTools is an open source, lightweight, modular object-oriented programming JavaScript web application framework released under the MIT License. The goal of the software is to provide a means for intermediate to advanced web developers to write cross-browser JavaScript in an elegant, flexible, and efficient fashion. The MooTools JavaScript framework includes built-in functions for manipulation of CSS, DOM elements, native JavaScript objects, Ajax requests, and more. MooTools also provides a detailed, coherent API to increase speed of development.

4. jQuery (http://jquery.com/)

Description:  jQuery is a lightweight JavaScript library that emphasizes interaction between JavaScript and HTML. It was released January 2006 at BarCamp NYC by John Resig.

Dual licensed under the MIT License and the GNU General Public License, jQuery is free, open source software.

Both Microsoft and Nokia have announced plans to bundle jQuery^[1] on their platforms, Microsoft adopting it initially within Visual Studio^[2] and use within Microsoft’s ASP.NET AJAX framework and ASP.NET MVC Framework whilst Nokia will integrate it into their Web Run-Time platform.

5.  MochiKit (http://www.mochikit.com/)

Description: MochiKit is a light-weight Javascript library written and maintained by Bob Ippolito.

Inspired by the Python networking framework, Twisted, it uses the concept of deferred execution to allow asynchronous behaviour. This has made it useful in the development of interactive web pages which maintain a dialog with the web server, sometimes called Ajax applications.

Of particular note is its ability to load and manipulate JSON-encoded data sets, and MochiKit.DOM, a set of functions to easily create dynamic page components.

MochiKit forms the foundation of the client-side functionality of the TurboGears Python web-application stack. Perhaps as a result of the author’s involvement in the Python community, MochiKit exhibits many idioms familiar to Python programmers, and is commonly used in Python-based web applications.

6. SproutCore (homepage: http://www.sproutcore.com/)

Description: SproutCore is an open-source JavaScript framework. Its goal is to allow developers to create web applications with advanced capabilities and a user experience comparable to that of desktop applications. When developing a SproutCore application, all code is written in JavaScript (including the view layer in 1.0). SproutCore, initially created in 2007 by Sproutit as the basis for their Mailroom application, is available under the MIT License.

Apple announced MobileMe at WWDC in 2008, noting that much of it was built using SproutCore. Apple has contributed greatly to the project as part of a Web 2.0 initiative. SproutCore is also used at iWork.com, the online extension of the iWork productivity software by Apple.

7. Spry (homepage: http://labs.adobe.com/technologies/spry/)

Description: The Spry Framework is an open source Ajax framework developed by Adobe Systems which is used in the construction of Rich Internet Applications. Unlike other pure JavaScript frameworks such as the Dojo Toolkit and Prototype, Spry is geared towards web designers, not web developers.

8. qooxdoo (homepage:http://qooxdoo.org/)

Description:  qooxdoo is entirely class-based and tries to leverage the features of object-oriented JavaScript. It is based on namespaces and does not modify or extend native JavaScript types. Most modern browsers are supported (Mozilla, Internet Explorer, Opera, Safari/WebKit, Chrome).^[1] It includes an API reference that is auto-generated from Javadoc-like comments. Among the accompanying tool set is a comprehensive JavaScript parser that is an integral part of the automatic build process and is used for optimizing, compressing, linking and the deployment of custom applications, as well as documentation generation. Internationalization and localization of applications are supported.

9. midori (homepage:http://www.midorijs.com/)

Description: midori is a lightweight JavaScript library that aims to make JavaScript web development easier. It was created by Aycan Gulez.

10. Archetype JavaScript Framework (homepage: http://archetypejs.org/)

Description: Archetype is build as a second level Framework, it needs an “engine” Framework to work. First based on Prototype , now, Archetype can work on top of differents Framework thanks to an abstract engine abstraction. Currently you can use both Prototype and jQuery wrappers. These frameworks helps a lot in JS development, providing really good features to Javascript in a navigator environnement. For us, if we were in a “Java” world, the engine would be “java.lang” so nothing but what’s needed to really start doing anything.

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