IRCd

An IRCd, meaning Internet Relay Chat server program, is a program, server software that uses the IRC protocol.  This allows people to talk to each other on the Internet.  They exchange textual messages in real time.

The server accepts connections from IRC clients on a group of TCP ports. When the server is part of an IRC network, it also keeps one or more connections with other servers/daemons.

The word ircd once referred to only one piece of software.

Related pages
 Comparison of Internet Relay Chat daemons

References

Other websites
 irc.org - IRC resources 
 Technical comparison of TS and nickname delay mechanisms 
 DarkFire IRC Manual (network specific) 
 IRCd network provider 
Undernet K-Line and G-Line FAQ  with reasons for them, amongst other things
EFnet FAQ  with several -line terms explained
Quakenet General FAQ G/K-Line
GLine, KLine, QLine and ELine syntax 

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