\"member\" or \"stranger\" are just titles. These titles depend on the number of posts you made. If you get to 25 posts you graduate from stranger to newbie. It is not important what title you have.
ICQ is a chat/InstantMessenger program similar (allthough not quite the same) to AIM, MSN Messenger. It is mainly used by computer nerds and other people who are on the internet for a long time, cause it was one of the first \"messenger\" or \"chat\" program around.
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