Leaving your
irc client connected to a server and sitting in channels even if you are not at the computer. This allows a group of users to stay in contact even if they are not active all the time.
Many misunderstand this concept and
think idling means to stare at an inactive channel for hours on
end but it just means leaving your client connected even if you
aren't there or are doing other things.
Note: things like the following would not be possible if both users were not idling.
9:56am <user1> so user2 how are
the girls?
1:12pm <user2> they are doing
great! i just got home.
1:12pm <user1> thats good. tell them
hi for me :)