IP.Board is commercial forum software from Invision Power Services, sold today as part of Invision Community. It runs on PHP with MySQL and is licensed rather than free.
How it models content
- Forums hold topics. Forums can be nested in categories.
- Topics hold posts. The first post is the one that opens the discussion.
- Posts are the individual replies.
- Members carry their own post counts, groups and permissions.
Invision Community is built as a set of applications sharing one member table, so a single install can run forums alongside a blog, a downloads area or a gallery. That matters when moving content out: what looks like one system is several content types side by side.
What moves cleanly
| Topics and posts | Map well onto any other forum |
| Members | Usually transfer, though passwords rarely do |
| Attachments | Need moving as files as well as database rows |
| Permissions and groups | Almost never map exactly. Expect to rebuild them. |
| Custom applications | No equivalent elsewhere |
Current status
Actively developed and sold as a licensed product, with self-hosted and cloud options. Because it is commercial, an expired licence stops updates, which is a common reason older installs get moved.