GNSS (Global Navigation Satellite System) is a satellite system that is used to pinpoint the
geographic location of a user's receiver anywhere in the world. Two GNSS systems are currently in
operation: the United States' Global Positioning System (GPS) and the Russian Federation's Global Orbiting
Navigation Satellite System (GLONASS). A third, Europe's Galileo, is slated to reach full operational
capacity in 2008. Each of the GNSS systems employs a constellation of orbiting satellites working in
conjunction with a network of ground stations.