JQuery Plug-ins
Because of jQuery's architecture, other developers can use its constructs to create plug-in code to extend its functionality. Currently there are thousands of jQuery plug-ins available on the web that cover a wide range of functionality such as Ajax helpers, webservices, datagrids, dynamic lists, XML and XSLT tools, drag and drop, events, cookie handling, modal windows, even a jQuery-based Commodore 64 emulator.
An important source of jQuery plug-ins is the Plugins sub-domain of the jQuery Project website. However, in an effort to rid the site of spam, the plugins in this subdomain were accidentally deleted in December 2011. The new site will include a GitHub-hosted repository, which will require developers to resubmit their plugins and to conform to new submission requirements. There are alternative plug-in search engineslike jquer.in that take more specialist approaches, such as listing only plug-ins that meet certain criteria (e.g. those that have a public code repository). The tutorials page on the jQuery site has a list of links to jQuery plug-in tutorials under the "Plugin development" section.
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