A chat room is a Web site, part of a Web site, or part of an online service such as America Online, that provides a venue for communities of users with a common interest to communicate in real time. Forums and discussion groups, in comparison, allow users to post messages but don't have the capacity for interactive messaging. Most chat rooms don't require users to have any special software; those that do, such as Internet Relay Chat (IRC) allow users to download it from the Internet.
Chat room users register for the chat room of their choice, choose a user name and password, and log into a particular room (most sites have multiple chat rooms). Inside the chat room, generally there is a list of the people currently online, who also are alerted that another person has entered the chat room. To chat, users type a message into a text box. The message is almost immediately visible in the larger communal message area and other users respond. Users can enter chat rooms and read messages without sending any, a practice known as lurking.
Because chat room messages are spontaneous and instantly visible, there is a potential for abuse, which may or may not be intentional. Site hosts typically post a frequently asked questions (FAQ) list to guide users to appropriate chat room behavior, such as introducing yourself when you enter a room, making it clear when you are directing a question or response to a specific user, and reporting disruptive users, for example. Disruptive users may verbally abuse other chatters, monopolize the conversation, or even just disable it by repeatedly typing the same word or phrase into the conversation, a practice (much frowned upon) known as scrolling.
Chat rooms can be found that focus on virtually any aspect of human endeavor or interest: there are current communities based on classic movies, Irish ancestry, baton twirling, and psychic readings, for example. Various sites, such as Yahoo, provide a directory of chat sites. Others, such as MSN Web Communities, guide users through the steps required to create their own chat room.