The forum module is probably one of the most complicated systems in DotNetNuke... and for good reason. It allows you to have multiple groups of multiple forums with multiple threads. It also allows you to have an Aggregated Forum (showing all the most recent posts in all forums). It supports Poster Ranking, Thread Classification, Thread Locking/Pinning, Post Rating, Avatars, Private Inboxes and Moderation. It also supports Polling, Word Filtering (Subject and Body) and Thread/Forum Notification settings.

Who ever built this thing was obsessed!

It also supports different Permissions for each forum... and you can have multiple views of the same Forum Module Hyperlinked by Group, Forum or Thread. This means you can have Public Readonly, Public Writable, Public Moderated, Private Readonly, Private Writable and Private Moderated all within the same group... and be able to guide members to View a Particular Group, Thread, or Post by URL.

When only ONE Forum Module is used in any Portal, It supports Thread Archiving (because Threads can be moved intact from a Writable forum to a ReadOnly forum. It also supports Author IP address Tracking and Post reporting (for multiple reasons).