Hey don't be embarassed, most people have used IRC without even knowing it.If you've ever used a chat room on a website, chances are you were on IRC unless the chatroom was flash-based (and even then). IRC stands for Internet Relay Chat and is actually quite old.
Depending on what IRC server you connect to, specific commands and designs may vary but the concept is the same. An IRC server is a house and the rooms are channels/rooms where people interact. Like a house they can't see other groups in rooms through walls and are usually confined to their own group rooms by default.
Or if you've used AIM/MSN/YIM just think of how you can join rooms and chat with others. Inherent to IRC is the ability to kick, ban, attribute rank... the list is a little long. If you look at my previous post, you'll see the different ways of accessing IRC.
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I found a fairly basic interface for everyone to check out, it's in my signature. Pick a nickname and check it out. I have a frame code for it if anyone wants it. Hopefully many people like it and then we can think about specific design for it. This is just to get a feel and it's based on AJAX.
Chat