What is GPS (Global Positioning System?)

GPS is a navigation system that relies on Satellite signals to show the location of an object

A GPS system uses a receiver, satellite & algorithms to synchronize time data, location and velocity for land, sea & air travel 

How GPS technology works?

It is the enhancement in GPS system which reduces delays & eliminates errors that occur in a GPS system during signals transit to earth

What is DGPS (Differential GPS)? 

Differential GPS (DGPS) uses a network of fixed, ground-based reference stations to find the location relative to a fixed point of reference

To read more about DGPS & how it is different from the Global Positioning System visit the link below

GPS v/s DGPS (Differential GPS)