The server listens to connections from IRC clients on a set of TCP ports. When the server is part of an IRC network, it also keeps one or more established connections to other servers/daemons.
The term ircd originally referred to only one single piece of software, but it eventually became a generic reference to any implementation of an IRC daemon. However, the original version is still distributed under the same name.
Jarkko Oikarinen (born 16 August 1967, in Kuusamo) is the developer of the first Internet chat network, called Internet Relay Chat (IRC), where he is known as WiZ. While working at Finland's University of Oulu in August 1988, he wrote the first IRC server and client programs, which he produced to replace the MUT (MultiUser Talk) program on the Finnish BBS OuluBox. Using the Bitnet Relay chat system as inspiration, Oikarinen continued to develop IRC over the next four years, receiving assistance from Darren Reed in co-authoring the IRC Protocol. In 1997, his development of IRC earned Oikarinen a Dvorak Award for Personal Achievement—Outstanding Global Interactive Personal Communications System; in 2005, the Millennium Technology Prize Foundation, a Finnish public-private partnership, honored him with one of three Special Recognition Awards.