The Free / Libre / Open Source Web App with the most built-in features
"Software made the wiki way"
A full-featured, web-based, tightly integrated, all-in-one Wiki+CMS+Groupware, Free Source Software (GNU/LGPL), using PHP, MySQL, Zend Framework, jQuery and Smarty. Tiki can be used to create all kinds of Web applications, sites, portals, knowledge base, intranets, and extranets.
Tiki is the Open Source Web Application with the most built-in features. Highly configurable and modular, all features are optional and administered via a web-based interface.
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pH7 Doc Script with support for multiple languages and Ajax navigation
Simple Navigation Documentation Script lets you easily create beautiful multilingual documentation for your software and lets you add some documentation files very easily and highlighting programming code.
This software has also an full Ajax navigation with HTML5 History / pushState URLs.