MediaWiki

MediaWiki is a wiki package originally written for Wikipedia. MediaWiki is an extremely powerful, scalable software and a feature-rich wiki implementation.

MediaWiki is a free wiki software application. Developed by the Wikimedia Foundation and others, it is used to run all of the projects hosted by the Foundation, including Wikipedia, Wiktionary and Commons. Numerous other wikis around the world also use it to power their websites. It is written in the PHP programming language and uses a backend database. The software's code is structured functionally.

Homepage: www.mediawiki.org/wiki/MediaWiki

The first version of the software was deployed to serve the needs of the free content Wikipedia encyclopedia in 2002. It has been deployed since then by many companies as a content management system for internal knowledge management. Notably, Novell uses it to operate several of its high-traffic websites. Thousands of websites use MediaWiki. Some educators have also assigned students to use MediaWiki for collaborative group projects.

The software is optimized to correctly and efficiently handle projects of all sizes, including the largest wikis, which can have terabytes of content and hundreds of thousands of hits per second. Because Wikipedia is one of the world's largest websites, achieving scalability through multiple layers of caching and database replication has also been a major concern for developers. Wikipedia and other Wikimedia projects continue to define a large part of the requirement set for MediaWiki.

The software is highly customizable, with more than 700 configuration settings and more than 1,800 extensions available for enabling various features to be added or changed. Only on Wikipedia, more than 1000 automated and semi-automated bots and other tools have been developed to assist in editing MediaWiki sites.

License
MediaWiki is free and open source software and is distributed under the terms of the GNU General Public License version 2 or any later version while its documentation is released under the Creative Commons BY-SA 3.0 license and partly in the public domain. Specifically, the manuals and other content at MediaWiki.org are Creative Commons-licensed, while the set of help pages intended to be freely copied into fresh wiki installations and/or distributed with MediaWiki software is public domain. This was done to eliminate legal issues arising from the help pages being imported into wikis with licenses that are incompatible with the Creative Commons license. MediaWiki development has generally favored the use of open-source media formats.
Development

MediaWiki has an active volunteer community for development and maintenance. Users who have made meaningful contributions to the project by submitting patches are generally, upon request, granted access to commit revisions to the project's Apache Subversion and now Git/Gerrit repository.There is also a small group of paid programmers who primarily develop projects for the Wikimedia Foundation. Wikimedia participates in the Google Summer of Code by facilitating the assignment of mentors to students wishing to work on MediaWiki core and extension projects. As of early November 2012, there were about two hundred developers who had committed changes to the MediaWiki core or extensions within the past year. Major MediaWiki releases are generated approximately every three to eight months by taking snapshots of the development trunk, which is kept continuously in a runnable state; minor releases, or point releases, are issued as needed to correct bugs (especially security problems).

MediaWiki has a public bug tracker, bugzilla.wikimedia.org, which runs Bugzilla. The site is also used for feature and enhancements requests.