The APRS system
Automatic Packet Reporting System (APRS) is a digital system that uses radio to send small packets of data to transmit information and messages over the amateur radio network.
The most common use for these small packets of data is to report the GPS co-ordinates and information which can then be decoded and mapped to show the position of the transmitting station.
APRS also makes use of the internet to relay the packets, this known as the APRS Internet Service (APRS-IS) – the use of the internet has spawned a number of websites displaying this data in real time, aprs.fi possibly being one of the best.
My latest APRS position data can be found HERE