A real time GPS tracking system works on the basis of GPS's radio navigation system. The small GPS device is set up within the vehicle, either by embedding or utilising a portable unit. All the information pertaining to the vehicle, from the location, speed to other data, is obtained with the help of the Global Navigation Satellite System (GNSS). With a host of satellites a part of this system, a GPS tracker provides you real time, as well as previously recorded data.