** Neill Newman neill@entora.co.uk [2004-01-19 06:03]:
Popular IRC clients include tkirc, bitchx, xchat and EPIC on Unix, and Mirc under windows. Here are some links to help you get started with irc.
Unix
http://www.xchat.org/ http://freshmeat.net/ http://www.epicsol.org/
Windows
http://www.mirc.com (loads of help with irc for newbies!)
** end quote [Neill Newman]
I was (am I guess) going to suggest adding that xchat is available for Windows too (and until switching to a combination of putty and irssi-text run using screen on one of my Linux boxes it was my primary Windows client). Having checked that it is available from the xchat.org site direct, and not a separate location (where I believe it started), I've found myself somewhat annoyed at the overkill use of popup advertising windows. Still that, doesn't affect the fact that it is quite a nice client - although my preference for it over mirc may be due to having started with irc on Linux and then looked for something for Windows (I can't remember what I did start with, but it was neither mirc or xchat - Visual IRC rings a bell, but that discontinued development in 1997!).
Oh, not wanting to try and cover all platforms in existance, but Mac clients may be worth adding too, particularly given the *nix'y roots of MacOS X. A quick Goolge showed up:
http://www.irchelp.org/irchelp/mac/