javascript
LESS extends CSS with dynamic behavior such as variables, mixins, operations and functions. LESS runs on both the client-side (IE 6+, Webkit, Firefox) and server-side, with Node.js.
Underscore provides 60-odd functions that support both the usual functional suspects: map, select, invoke — as well as more specialized helpers: function binding, javascript templating, deep equality testing, and so on. It delegates to built-in functions, if present, so modern browsers will use the native implementations of forEach, map, reduce, filter, every, some and indexOf.
Spin.js uses the CSS3 to render the UI, falling back to VML Internet Explorer. If supported by the browser, @keyframe rules are used to animate the spinner.
Raphaël is a small JavaScript library that should simplify your work with vector graphics on the web. If you want to create your own specific chart or image crop and rotate widget, for example, you can achieve it simply and easily with this library.
Créez votre RPG sur navigateur en HTML5 !
Buzz is a small but powerful Javascript library that allows you to easily take advantage of the new HTML5 audio element. It degrades properly on non-modern browsers.
Tangle is a JavaScript library for creating reactive documents. Your readers can interactively explore possibilities, play with parameters, and see the document update immediately. Tangle is super-simple and easy to learn.
jquery.qrcode.js is jquery plugin for a pure browser qrcode generation. It allow you to easily add qrcode to your webpages. It is standalone, less than 4k after minify+gzip, no image download. It doesnt rely on external services which go on and off, or add latency while loading. It is based on a library which build qrcode in various language. jquery.qrcode.js wraps it to make it easy to include in your own code.
Spine is a lightweight framework for building JavaScript web applications. Spine gives you a MVC structure and then gets out of your way, allowing you to concentrate on the fun stuff, building awesome web applications.
WebODF is a JavaScript library that makes it easy to add Open Document Format (ODF) support to your website and to your mobile or desktop application. It uses HTML and CSS to display ODF documents.
Full month calendar jQuery plugin that looks like Google Calendar.
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.