GPS navigation device
A GPS navigation device is a device that accurately calculates geographical location by receiving information from GPS satellites. Initially it was used by the United States military, but now most receivers are in automobiles and smartphones.
The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of a minimum of 24, but currently 30, satellites placed into orbit by the U.S. Department of Defense. Military action was the original intent for GPS, but in the 1980s, the U.S. government decided to allow the GPS program to be used by civilians. The satellite data is free and works anywhere in the world.
GPS devices may have capabilities such as:
maps, including street maps, displayed in human readable format via text or in a graphical format,
turn-by-turn navigation directions to a human in charge of a vehicle or vessel via text or speech,
directions fed directly to an autonomous vehicle such as a robotic probe,
traffic congestion maps (depicting either historical or real time data) and suggested alternative directions,