Hello Jun Xie, Most Chinese use QQ , but you better download others mentioned by Jennifer, because you will be mostly communicating with Native English speakers who hardly use QQ.

i use QQ^^

Yeah, most people outside of China use: skype: http://www.skype.com msn: http://download.live.com/messenger yahoo: http://messenger.yahoo.com/download aim: http://download.aim.com/client/70 If you want a multichat client that is open source, you can use: pidgin: http://www.pidgin.im/download/ For people who want to use the international QQ though, it's now here: QQ: http://www.imqq.com/download.shtml They don't have a mac version yet though...

How about other chat tool such as "MSN" or "Skype" or even "Yahoo Messenger"? Not many use "QQ".