IRC

IRC (Internet Relay Chat) is the forebear to modern chat and instant messenger services, created by Jarkko "WiZ" Oikarinen of the University of Oulu, Finland in 1988. IRC is a set of client-server protocols and software that allow users to connect to servers linked together in a network and then exchange messages with other users in chat rooms, called "channels" or with other users as private messages and exchange files through a protocol called DCC.

Connecting to an IRC network requires an IRC client, which sends and receives messages to and from an IRC server. Usually clients are either standalone programs, or web-interfaces that work straight in your browser.

IRC and furry
Two major furry IRC networks exist: Anthrochat and FurNet. Furtopia also runs their own IRC network.

IRC clients

 * List of IRC clients on Wikipedia