MediaWiki

=MediaWiki= []
 * Software systems / MediaWiki**

MediaWiki was explicitly developed for Wikipedia and is used by all wikis of the Wikipedia Foundation and all wikis hosted on Wikia. It has also been deployed in corporate environments for knowledge management. As the name suggests it supports a wide range of media types. It is free of charge and open source (GNU GPL), and is written in PHP, using either MySQL or PostgreSQL for data storage. The focus on the needs of Wikipedia mean that its strengths are in scalability, rich media support and multilingualism/localization (the interface exists in about 300 localized version).
 * Various mechanisms of caching and database replication are used to support high levels of usage (Wikipedia gets up to 60,000 queries per second)
 * There is a rich, if complicated, mark-up language which provides automation of many link features.
 * Simple generation of image galleries.
 * The editor has no native WYSIWYG support, though Wikia has deployed an extension based on FCKeditor.
 * Parts of a page can be edited separately.
 * Extensive support for templates which provide regularised structure for page elements in frequent use (e.g. InfoBoxes). These are also used to insert alerts into pages which fail to meet Wikipedia’s editing criteria.
 * Namespaces separate page content from the content of e.g. discussion pages.
 * There is not a strong emphasis on access control, though pages can be ‘protected’ if they prove subject to abuse.

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