The Global Positioning System (GPS) is a constellation of 24 satellites, that provide information to a GPS receiver, so that software in the receiver can determine a position in three dimensions (altitude, latitude, and longitude).

Originally developed by the U.S. Department of Defense for use in precision weapon delivery, the initial satellites were launched between 1974 and 1977. During the Clinton administration, use of the system's additional bandwidth was opened for civilian use. This move, combined with recent advances in personal technologies were the catalyst for an explosive surge in GPS market opportunities and intelligent applications.