AROIP (Amateur Radio over Internet Protocol) means IP-based communication among radio amateurs using officially registered amateur radio callsigns. AROIP works wire-bound (CQ100, HamSphere, EchoLink, Mototrbo...) as well as wireless (HamNet).
There is now an easy way to teletype the whole amateur radio world by means of Etherpad Lite: Go to http://etherpad.tugraz.at
, login with "ham" (without quotes), click OK and start qsoing with the radio amateurs online. If there is nobody online you may drop a line and try later on...
73, Alfred, OE5AKM