An online forum, also known as a message board or discussion board, is a platform where people can have discussions and exchange ideas on a particular subject or topic. Forums are usually organized around a specific topic or theme, and users can post messages and reply to others' messages in the form of a discussion thread. Many forums also have additional features, such as the ability to upload files, create polls, and rate or review content. Online forums are a popular way for people to connect with others who have similar interests and to share information and opinions on a wide range of topics.