Wiki

A wiki is a website that anyone can edit. For more information, see the article about wikis on Wikipedia, the wiki-based free encyclopedia.

Wikis with Doom content:
 * This project, the Doom Wiki (http://doom.wikia.com/)
 * The ZDoom documentation project (http://zdoom.org/wiki/)
 * The Doom Legacy Wiki (http://legacywiki.net/) &mdash; note that this is not GFDL, and material from the Legacy Wiki should not be copied into the Doom Wiki
 * The Eternity Wiki (http://eternity.youfailit.net/)
 * The Vavoom Wiki (http://www.vavoom-engine.com/wiki/)
 * The DoomRL Wiki (http://doomwiki.chaosforge.org/)
 * The Doomsday Engine Wiki (http://dengine.net/dew/)

Wikipedia also has a fair amount of Doom coverage; see, for example, Category:Doom.