Global Positioning System (GPS) uses the signals from
geosynchronous satellites to provide accurate position information
for navigation. As such utilizing GPS for navigation amounts to
utilizing satellite navigation ("sat nav").
Note that while GPS, which was developed by the US government is
the most widely used satellite navigation system, Russia also has
the Global Navigation Satellite System (GLONASS) deployed which can
provide essentially the same satellite navigation capabilities -
and can be used in along with GPS to get faster and more accurate
position information. The EU, Japan, China, and India are also
working to deploy a satellite navigation systems.