Hello,
How GPS Navigation work
Either it has info or it can spot all ways on map.
It can spot where are you through your receiver and displays the position of your device and map of place around this. This is called Satellite Navigation System. Many countries have their own systems to help their civilians and tourists and support their military as well.
USA-
GPS(Global Positioning System)
European Union-
Galileo
Russia-
GLONASS(Global Satellite Navigation System)
China-
BeiDou- 1(regional system, can serve only in Asia Pacific and South Asia)
BeiDou-2(Global Range, currently in development) planned for 2020,
India'
IRNSS(Indian Regional Navigation Satellite System)
Currently in final stage of development and covers South Asia(will be completed in March 2016).
Later, it's range will be extended to cover Asia Pacific also to match with BeiDou-1.
A Global Range system is planned for long term after executing important missions.