Wikkawiki is a flexible, standards-compliant and lightweight wiki engine written in PHP, which uses MySQL to store pages. Designed for speed, extensibility, and security.
Features
Support for different types of embedded
User-selectable and modular theme support.
Administration modules to manage pages and users, including tools for bulk operations like user removal or page reversion.
Advanced (but optional) access control, with user registration, password management and provision for user profiles, as well as access control lists for page access.