Triangulation

Triangulation is a process whereby a location is calculated from the calculation of distance from at least three known positions (hense the tri in in the name). This process is used by a GPS system, which take time readings from satalites in specific known positions around the unit, and from that time (and with the knowledge of the speed at which the transmission is executed) can calculate their distances from the satelites. They can then extrapolate their height above sea level, and more importantly their current world co-ordinates.

This would seem to have nothing to do with CCIT, and I'm not sure why this is here :)