what is irc and how it use it?
irc or Internet Relay Chat is something like yahoo or gtalk chat but it’s public and every one can join/view or create it.
there is a irc server(like irc.example.com/482 (ex:irc.freenode.net/8001 ports to use for freenode 6665, 6666, 6667, 8000, 8001, 8002 and ssl= 6697, 7000, 7070 )) and some client applications to use it like xchat.

here is some most used comments on a irc channel:

get a nickname:

/nick mee

using the irc you need to create an account:

/msg NickServ REGISTER mypassword youremail@example.com

hide your email:

/msg NickServ SET HIDEMAIL ON

to make your ip hidden ask for a admin to cloak you
sign in again:

/msg NickServ IDENTIFY password

get info about a channel

/msg ChanServ info #channelname

create a channel (mostly used for organisation):

/join #channelname

register your channel:

/msg ChanServ register #channelname

to chose a topic

/msg ChanServ topic #channelname message

auto operator:

/msg chanserv flags #channelname me +O

keeps your channel up when there are 0 people in room

/msg chanserv set #channelnam guard on

keeps your channel’s topic when there are 0 people in room

/msg chanserv set #channelnam keeptopic on

delete it:

/msg chanserv `drop`

help:

/msg chanserv help