An Internet forum is a web application for holding discussions and posting user-generated content. Internet forums are also commonly referred to as Web forums, message boards, discussion boards, (electronic) discussion groups, discussion forums, bulletin boards, fora (the Latin plural) or simply forums. The terms "forum" and "board" may refer to the entire community or to a specific sub-forum dealing with a distinct topic. Messages within these sub-forums are then displayed either in chronological order or as threaded discussions.
Such forums perform a function similar to that of Usenet newsgroups and the dial-up bulletin board systems that were common from the late 1970s to the 1990s. Early web-based forums date back as far as 1996. A sense of virtual community often develops around forums that have regular users. Technology, computer games and/or video games, sports, fashion, religion, and politics are popular areas for forum themes, but there are forums for a huge number of topics. Internet slang and image macros popular across the internet are abundant and widely used in internet forums.

Membership and anonymity

Anonymous forums may offer full anonymity or pseudonymity, allowing posts without registration. Captchas, e-mail authentication, and tripcodes are often used to prevent comment spam on such forums.
Registered members of a forum, who are identified by unique usernames, may have additional privileges, such as the ability to edit their previous posts, start new topics, and control their individual settings and profiles. The profiles tend to include graphical avatars and signature blocks which are appended to their future posts, sometimes consisting of elaborate shoutboxes. Members also have the ability to send personal messages to each other. In certain cases, members have been given the ability to close their own topics, edit previously posted comments, or delete posts in topics they have started.
Western-style forums place heavy emphasis on identity and user registration. This makes the tone of discussion very different from the more anonymous 2channel style boards. The burdens of status and persona encourage both highly formal discourse and close personal relationships, depending on the tone given a forum by its moderators and heaviest users. The permanence of messages on many western-style forums can encourage users to self-moderate. Precursor systems like Usenet have been archived as far back as 1981 by Google Groups (formerly DejaNews).

Administrators and moderators

A forum administrator typically has the ability to edit, delete, move or otherwise modify any thread on the forum. Administrators also usually have the ability to close the board, change major software items, change global skins, modify the board, and ban, delete, or create members. Moderators have a subset of these powers, which may include editing, deleting, and moving threads, mass pruning, warning members for offences, and changing minor forum details. It is often possible for moderator privileges to be delegated to other forum members.
A board's moderation system can include moderation of the moderators via a meta-moderation system. The board software may also allow administrators to create wordfilters, automated scripts which strip undesirable text from users' messages. Other features may include sticky threads, allowing moderators and administrators to cause significant threads to display at the top of the forum's index.