Database Required
ErfurtWiki
From ErfurtWiki Site:
"ErfurtWiki is a fast, user-friendly, and highly configurable hypertext management system. It can store its pages and binary content with MySQL, PEARDB/dbx/ADOdb, dba/dbm, PHP-RPC, or flat file databases. It stands out from similar Wiki implementations in that it allows very easy integration into existing Web sites, features case-insensitive WikiLinks, extensive CSS support, multiple admin tools, is not GPLed, and includes documentation. There are over 200 extension plugins, but everything could still be compacted into one core "library" for easier installation and handling. It is useful for larger sites as well as lightweight backend for private homepages, due to its simple image uploading feature."
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Currently Unavailable Visit Site
Helpful Resources:
ErfurtWiki Developer Site
ErfurtWiki Sourceforge Page
ErfurtWiki Freshmeat Listing
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Installation:
License:
MediaWiki
From MediaWiki Site:
"The Wikimedia Foundation, Inc. is a non-profit foundation registered in the state of Florida which operates Wikipedia (a free encyclopedia in over 50 languages), Wiktionary (a free dictionary), Wikisource (a collection of public domain or FDL-licensed texts), Wikibooks (free textbooks for schools and universities), and Wikiquote (a collection of notable quotations).
All these projects are based on wiki technology: they are open knowledge bases which can be improved by anyone. This is the homepage of the underlying open source wiki engine, MediaWiki, which is developed here on SourceForge via CVS, and is available under the GNU General Public License (the contents of the Wikimedia wikis themselves are licensed under the GNU FDL)."
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Edit Page Screenshot:

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Frequently Asked Questions:
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Helpful Resources:
MediaWiki Developer Site
MediaWiki Sourceforge Page
MediaWiki Freshmeat Listing
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Installation:
License:
phpWiki
From phpWiki Site:
"PhpWiki is a clone of the original WikiWikiWeb."
Features:
There is currently no feature list available. Visit Site
User Screenshot:

Demo Link:
Documentation:
System Requirements:
There is currently not a list of system requirements for phpWiki. Visit Site
Helpful Resources:
phpWiki Developer Site
phpWiki Sourceforge Page
phpWiki Freshmeat Listing
Download:
License:
UniWakka
From Uniwakka Site:
"UniWakka is a Wiki Engine derived from WakkaWiki, a light-weight, easy to install and to configure collaborative editing software for web content.
Derived from Wakka-0.1.3-dev, UniWakka is mostly intended for an university or scientific environment."
Features:
User Screenshot:

Demo Link:
Documentation:
There is currently no documentation for this project. Visit site for info.
System Requirements:
Helpful Resources:
UniWakka Developer Site
UniWakka Sourceforge Page
Download:
License:
TikiWiki
Note: Although better described as a Content Management System (CMS), TikiWiki is included here because of its wiki capability.
From the TikiWiki Site:
"Tiki CMS/Groupware (aka TikiWiki) is a powerful open-source Content Management System (CMS) and Groupware that can be used to create all sorts of Web applications, Sites, Portals, Intranets and Extranets. TikiWiki also works great as a Web-based collaboration tool. TikiWiki is a multi-purpose package with a lot of native options and sections that you can enable/disable as you need them. It is designed to be international, clean and extensible.
TikiWiki incorporates all the features present in several excellent wiki systems available today plus a lot of new features and options, allowing your wiki application to be whatever you want it to be--from a simple wiki to a complex site for a whole user community with many intermediate steps. You can use TikiWiki as a forums site, a chatroom, for poll taking, and much more! The possibilities are endless.
TikiWiki's major features include: article, forum, newsletter, blog, file/image gallery, wiki, drawing, tracker, directory, poll/survey, quiz, FAQ, chat, banner, webmail, calendar, category, ACL, and more."
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Helpful Resources:
TikiWiki Developer Site
TikiWiki Sourceforge Page
TikiWiki Freshmeat Listing
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License:
WackoWiki
From WackoWiki Site:
"Small, lightweight, handy, expandable, multilingual Wiki-engine based on Wakka Wiki. WYSIWYG editor, easy installer, many localizations, email notification on changes/comments, several cache levels, design themes (skins) support, XHTML compliance, page rights (ACLs), page comments and is distributed under the BSD License."
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Helpful Resources:
WackoWiki Developer Site
WackoWiki Freshmeat Listing
Download:
http://wackowiki.com/WackoDownload/InEnglish
License:
WikkaWiki
From WikkaWiki Site:
"WikkaWiki is a flexible and lightweight wiki engine written in PHP, which uses MySQL to store pages. Forked from WakkaWiki. Designed for speed, extensibility, and security. Released under the GPL license."
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Helpful Resources:
WikkaWiki Developer Site
WikkaWiki Freshmeat Listing
WikkaWiki Bugtracking, New Feature Suggestion and svn Repository
WikkaWiki Info Page on Wiki Matrix
WikkaWiki Forum on Wiki Matrix
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License:
WikkiTikkiTavi
From the WikkiTikkiTavi Site:
"WikkiTikkiTavi is a wiki engine --- it is a PHP script that runs wiki sites. Wikis are a revolutionary new form of collaboration and online community. Although there exist many WikiEngines and wikis around the world, this wiki is dedicated to the WikkiTikkiTavi and those of you who might want to use it for your wiki.
Why is it called WikkiTikkiTavi? It's a reference to the character Rikki-tikki-tavi, a mongoose whose [story] was told by Rudyard Kipling in the second of his [Jungle Books]. He was a brave mongoose, living the true mongoose spirit, the way WikkiTikkiTavi tries to live the TrueWikiSpirit."
Features:
Full WikkiTikkiTavi Feature List
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Demo Link:
Documentation:
System Requirements:
WikkiTikkiTavi System Requirements
Helpful Resources:
WikkiTikkiTavi Developer Site
WikkiTikkiTavi Sourceforge Page
WikkiTikkiTavi Freshmeat Listing
Download:
http://tavi.sourceforge.net/TaviDownload
License: