The IRC technology is older than the newer Web-based chat technology. IRC uses a text-based communication protocol on a client/server network. The server computer connected to the Internet hosts multiple IRC connections. The users connect to this server with specialized software that resides on their client computer. Because the server can host multiple simultaneous connections, users can communicate with each other by passing messages to the server which relays the messages to all users currently logged on to the IRC channel. An IRC channel is similar to a room where a group of users meet. Channels are given a name by the user who creates the channel, who is known as the channel operator. Subsequent users must JOIN the channel to participate. The channel may be restricted to only users who have been invited. > Source