Wikia (formerly known as Wikicities) is a wiki hosting service created in 2004 by Jimmy Wales and Angela Beesley. It is a collection of wikis running on MediaWiki software and operated by Wikia, Inc. that target different communities. It is free of charge for readers and editors, and gets its income from advertisements. As of mid-2006 its Alexa Internet traffic ranking was around 3000. AdSense advertisements are present in most of its wikis.

Wikia allows a broad range of requests to start a new community project. With the exception of ideas that might compete with the Wikimedia projects, which the Wikia founders are heavily involved in, most broadly scoped projects are acceptable. Wikia requires all content to be licensed under GNU Free Documentation License (GFDL) or multi-licensed under GFDL and another free content licence. Wikia also has some crossover with Wikipedia, with the communities of Wikia being linked on the relevant Wikipedia article in many cases.

Some popular communities on the site are the wikis for Lost Star Wars (Wookieepedia) Doctor Who ^*," target="_blank" >non-canonical Star Trek Memory Alpha), the Psychology Wiki ^*" target="_blank" >the Apple Macintosh 24 ^*," target="_blank" >Doom Christianity ^*," target="_blank" >The X-Files Micronations [http://micronations.wikia.com" target="_blank" >^*.

Wikia runs on MediaWiki software on Linux servers. The project announced the creation of its Press releases/February 2005 wiki on February 3 2005. As of March 2006, it had over 1000 wikis in 35 different languages. Wikia provides both technical and social support for all aspects of running a wiki community.

On March 27 2006, WikiCities changed its name to Wikia to prevent confusion; some had mistakenly thought that WikiCities provided city guides. Following the change in name, Wikia announced that it had received US$4 million in venture capital from a group of investors.

Wikiasari was a project run by Wales that attempted to create a copyleft search engine. The Wikiasari project used to be called Wikia.

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