A forum is a discussion platform where related ideas, thought and, views on a particular issue can be exchanged. You can set up a forum for your site or blog, where your team, customers, fans, patrons, audience, users, advocates, supporters, or friends can hold public or private discussions, as a whole or in smaller groups.
1 Phorum – Forum Software
Phorum is a free open source, simple, highly-customizable, and easy-to-use PHP message board software. It has a very flexible hook and module system for you to customize your web community discussion platform.
2. Vanilla – Modern Community Forum
Vanilla is an open source, fully-featured, intuitive, robust cloud-based and multi-lingual community forum software. It is easy to use giving users a modern forum experience, allows users to post questions and polls; it has an advance editor for formating posts with html, markdown, or bbcode, and supports @ mentions.
3 Discourse – Discussion Platform
4 miniBB – Community Discussion Forum
miniBB is a free open source, standalone, lightweight, fast, and highly customizable software for building a web forum. It is suitable and effective for setting up a simple and stable community discussion platform, especially for novices. It allows for dynamic and content-rich discussions, and you can enable it to be responsive via the mobile template. It can easily be integrated with your website, allowing you to change its layout to the look of your website. In addition, miniBB offers facilities for you to synchronize with an existing membership system. Importantly, it supports guest posts and quick moderation.
5. SimpleMachinesForum (SMF)
SimpleMachinesForum is a free, open source, simple, beautiful and powerful forum software. It is available in over 45 different languages. SMF is easy to use and highly customizable, with a multitude of powerful and effective features. It comes with high quality and reliable support. SMF is highly customizable; it has many extensions/packages (under various categories such as security, socialization, administration, permissions, posting, theme enhancements and more) to modify its core functionality, add or remove features, and lot more.