phpBB

phpBB is an open source forum application. Initially released in 2000, phpBB is currently the most used free forum application with millions of people using the application every day.

phpBB is a high powered, fully scalable, and highly customisable open-source bulletin board package. Whether you want to stay in touch with a small group of friends or are looking to set up a large multi-category board for a corporate website, phpBB has the features you need built-in.

Newer users will appreciate phpBB's extensive administration panel, which allows the customisation of even the most intricate features without having to edit code directly while advanced users will value the ease with which phpBB can be integrated into existing systems.

Features:

• Enables community discussion through an intuitive interface.
• Multiple discussion forums and categories are supported for maximum flexibility.
• Anti-spam tools keep every board free of unwanted users and spam.
• Share files by uploading and attaching them to posts.
• Moderators can help to maintain order by assisting users and enforcing the rules.
• Private messages are direct messages between two or more users.
• An advanced caching system is utilized to increases board performance.
• Straightforward administration settings enable full control over the look, feel, and operation of every board.
• User groups enable users to easily be organized, and then the administrator can fine tune where users can go and which features they can use.
• The powerful search system enables users find topics, posts, and users.
• A powerful plugin system can be used to extend phpBB's functionality.