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.^[1]

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.^[2]

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

• Comparison of Internet Relay Chat daemons

1. ↑ "IRC Server Request FAQ". Archived from the original on 2009-04-22. Retrieved 2009-05-10.
2. ↑ "IRCD FAQ on irc.org". Archived from the original on 2009-04-19. Retrieved 2009-05-10.

• irc.org - IRC resources Archived 2011-02-21 at the Wayback Machine
• Technical comparison of TS and nickname delay mechanisms Archived 2007-04-12 at the Wayback Machine
• DarkFire IRC Manual (network specific) Archived 2008-04-04 at the Wayback Machine
• IRCd network provider Archived 2016-03-04 at the Wayback Machine
• Undernet K-Line and G-Line FAQ Archived 2008-04-01 at the Wayback Machine with reasons for them, amongst other things
• EFnet FAQ Archived 2008-08-27 at the Wayback Machine with several -line terms explained
• Quakenet General FAQ G/K-Line
• GLine, KLine, QLine and ELine syntax Archived 2008-03-23 at the Wayback Machine