Simple Machines Forum
Free, open-source PHP forum software with multiple database backends.

Simple Machines Forum (SMF) is an open-source bulletin board software written in PHP. It provides a scalable, feature-rich platform to run online communities with forums, topics, user roles, moderation, and a modular addon system.
Key Features
- Uses PHP and MySQL, PostgreSQL, or SQLite for data storage.
- Newly developed template system to simplify customization and theming.
- Advanced permissions and multi-language support for diverse communities.
- Package Manager to install/uninstall mods and themes with a few clicks.
- Rich posting features including WYSIWYG editing, BBCode, spell check, and attachments.
- Moderation tools and a dedicated moderation center for staff workflows.
- Attachments, polls, calendars, and RSS/XHTML outputs for rich content and engagement.
- External integration via SSI to embed recent topics, polls, and news into other websites.
- Open-source with well-documented source code and community-driven enhancements.
Use Cases
- Build a public or private forum for a community or business with multi-board structure and granular permissions.
- Embed forum content into an existing website using SSI to display recent topics, polls, or news.
- Run a moderated community with attachments, polls, and calendars to coordinate events and discussions.
Limitations and Considerations
Conclusion
SMF offers a mature, lightweight forum solution with a modular extension system and broad database support, suitable for small to mid-sized online communities.
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