If you’re a subscriber to Website Magazine’s bi-weekly Design and Development Digest, you are familiar with jQuery (and its many plugins), a lightweight JavaScript library that emphasizes interaction between JavaScript and HTML. While it’s one of our favorite ways to add some real punch to your website and make the on-site experience for users that much richer (search ’jQuery’ at WebsiteMagazine.com), there are many solid alternatives in use by designers and developers worldwide. Let’s look at three, in MooTools, YUI and the Prototype Javascript Framework.

The Prototype JavaScript Framework provides an Ajax framework (and other utilities) implemented as a single file of JavaScript code, usually named prototype.js. Prototype is distributed standalone (prototypejs.org), but also as part of larger projects such as Ruby on Rails, script.aculo.us and Rico. Prototype provides various functions for developing JavaScript applications, and features range from programming shortcuts to major functions for dealing with XMLHttpRequest.

The Yahoo! UI Library (YUI) is an open-source JavaScript library for building rich, interactive Web applications using techniques such as Ajax, DHTML and DOM scripting. YUI includes several core CSS resources and is actively developed by a team of Yahoo! engineers. The YUI project (developer.yahoo.com/yui/) includes the YUI Library and two build-time tools: YUI Compressor (minification) and YUI Doc (documentation engine for JavaScript code.)

MooTools (mootools.net) is another opensource jQuery alternative. The compact JavaScript framework is designed for the intermediate to advanced JavaScript developer and is both extensive and modular, giving developers the ability to choose components appropriate to the project. It allows you to write powerful, flexible, and cross-browser code with its elegant, well documented, and coherent API.