Confluence vs Mediawiki

Confluence provides one place for technical teams to collaborate—create, share, and discuss your ideas, files, minutes, specs, mockups, diagrams, and projects. A rich editor, deep Office and JIRA integration, and powerful plugins help teams collaboratively develop technical docs, intranets, and knowledge bases. Confluence free alternatives are: XWiki, MediaWiki, dokuwiki.
MediaWiki is a popular free web-based wiki software application. Developed by the Wikimedia Foundation, it is used to run all of its projects, including Wikipedia, Wiktionary and Wikinews. It is written in the PHP programming language and uses a backend database.