DokuWiki is a wiki application licensed under GPL 2 and written in the PHP programming language. It works on plain text files and thus does not need a database. Its syntax is similar to the one used by MediaWiki.
DokuWiki was created by Andreas Gohr in June 2004. In July the first official release was published on Freshmeat (now known as Freecode). A big step in the development was the re-design of the parser and the renderer in January 2005. The new design was a big performance improvement and made DokuWiki usable for bigger documentation projects. It also prepared DokuWiki for an introduction of a generic plugin interface which simplified the development and maintenance of add-ons. A push of the level of awareness was the introduction of DokuWiki in the Linux distributions Debian in April and Gentoo Linux in July 2005. Since 2005, it has achieved significant usage.
DokuWiki stores all versions of each wiki page, allowing the user to compare the current version with any older version. The difference engine is the same as the one used in MediaWiki. Parallel editing of one page by multiple users is prevented by a locking mechanism.
Access control can be handled by a user manager which allows users and groups of users to be defined, and an access control list where an admin user can define permissions on page and namespace level, giving it much better access control than Mediawiki.
DokuWiki has a generic plugin interface which simplifies the process of writing and maintaining plugins. There are ~1000 plugins available. These can be easily integrated and managed by an admin user with the help of the plugin manager.