MediaWiki is perhaps the best known wiki platform, as it is the software used for Wikipedia (http://www.wikipedia.org) and the other Wikimedia Foundation websites. It is designed specifically for high traffic websites using multiple servers. It can be used for smaller applications, but the installation process can be complicated compared to other wikis. MediaWiki is open source software that can be freely downloaded. It is also available as a hosted service through http://www.wikia.com