A discussion board (known also by various other names such as discussion group, discussion forum, message board, and online forum) is a general term for any online "bulletin board" where you can leave and expect to see responses to messages you have left. Or you can just read the board. The first discussion boards were available on bulletin board systems. On the Internet, Usenet provides thousands of discussion boards; these can now sometimes be viewed from a Web browser.
Many websites offer discussion boards so that users can share and discuss information and opinions. Special software is available that provides discussion board capability for a website.