MediaWiki is a free software open source wiki package written in PHP, originally for use on Wikipedia. It is now also used by several other projects of the non-profit Wikimedia Foundation and by many other wikis, including this website, the home of MediaWiki.

TiddlyWiki, a unique non-linear notebook for capturing, organizing and sharing complex information. Use it to keep your to-do list, to plan an essay or novel, or to organize your wedding. Record every thought that crosses your brain, or builds a flexible and responsive website.