WikkaWiki

WikkaWiki is a flexible, standards-compliant and lightweight wiki engine written in PHP and using MySQL to store pages. Designed for speed, extensibility, and security. Released under the GPL license. WikkaWiki is among the most popular open source wiki engines, with a large userbase and a regular release cycle (2-3 upgrades per year). It powers thousands of wikis in 37 languages° and is used as a lightweight knowledge management system by large companies (such as Apple, IBM, Alcatel, ABN Amro, HSBC), universities (including Harvard, MIT, CalTech, UCLA, GMU, ETH Zürich) and scientific consortia (such as the Global Biodiversity Information Facility).