Overview
jQuery is an absolute requirement for any browser-based application or site. Why write 100 lines of DOM manipulation code using the W3C API when you can do the same work in 3 lines of jQuery? Plus, there are hundreds if not thousands of jQuery-based plugins available, many either free or modestly priced. These plugins solve common problems so that you don't have to.
The jQuery Cheatsheet is a great resource for summarizing the functionality that jQuery provides. It categorizes all of the jQuery entry points into useful categories (Selectors, Attributes, Manipulation, Traversing, Events, Effects, Ajax, Core) and provides a useful search ability:
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The cheatsheet supports the following configuration options:
Try it yourself right now!