11. But what's already included in my distribution ? (Linux on x86)

11.1. Debian

IRC Channel: #Debian on freenode (irc.debian.org -> irc.freenode.net)

Debian - http://www.debian.org/ includes too many IRC tools to list. You can find them at the following places:

11.2. Fedora (Red Hat)

IRC Channel: #RedHat on freenode (irc.redhat.com -> irc.freenode.net)

Fedora Core 3 includes the following clients:

11.3. Slackware

IRC Channel: #Slackware on freenode and OFTC - http://www.oftc.net/

Slackware - http://www.slackware.com/ 10.0 includes the following clients: