Satellite navigation
Satellite navigation (satnav) or satellite positioning is the use of artificial satellites for navigation or geopositioning. A global navigation satellite system (GNSS) provides coverage for any user on Earth, including air, land, and sea. There are four operational GNSS systems: the United States Global Positioning System (GPS), Russia's Global Navigation Satellite System (GLONASS), China's BeiDou Navigation Satellite System (BDS), and the European Union's Galileo.
Source: Wikipedia
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply.