ircII

ircII (pronounced i-r-c-two, and sometimes referred to as IRC client, second edition) is a free, open-source Unix IRC and ICB client written in C. Initially released in the late 1980s, it is the oldest IRC client still maintained. Several other UNIX IRC clients, including  BitchX, EPIC, and ScrollZ, were originally forks of ircII. For some, ircII set the standard of quality for IRC clients, however other clients have since overtaken ircII in terms of popularity. The application has been promoted as being "fast, stable, lightweight, portable, and easily backgrounded".