Using a GPS for Hiking
GPS is an acronym for Global Positioning System. Though there are many components to the system, the essential elements are:
a) a series of satellites, and
b) the actual GPS units that people carry.
Three satellites are used to locate your position across the Earth’s surface and another can be used with them to calculate your altitude in a process called triangulation. GPS units come in an array of prices, with the higher priced models offering more features. Read the full article Using a GPS for Hiking