GPS stands for Global Positioning System, and it is a system made up of three parts: satellites, ground stations, and receivers. GPS is a U.S. government satellite-based navigation system that currently consists of at least 24 operational satellites. GPS works by constantly sending out signals from over 30 navigation satellites circling Earth. A GPS receiver in your phone or other device can pick up these signals and calculate its distance from four or more satellites to determine its exact location on the ground with incredible precision, usually within a few yards of the actual location.
GPS answers five questions simultaneously: "Where am I?", "Where am I going?", "Where are you?", "Whats the best way to get there?", and "When will I get there?". GPS is the only system today that can show your exact position on the Earth anytime, in any weather, no matter where you are.
GPS is used in many different industries, including surveying, science, aviation, marine archaeology, and mining. GPS is built into all types of devices, such as smartphones, smartwatches, automobiles, boats, and more. To calculate your 2D position (latitude and longitude) and track movement, a GPS receiver must be locked onto the signal of at least three satellites. With four or more satellites in view, the receiver can determine your 3D position.
