GlobalPositioningSystem(GPS)isasatellite-basednavigationsystemthatprovideslocationandtimeinformationanywhereonorneartheEarthwherethereisanunobstructedlineofsighttofourormoreGPSsatellites.DevelopedandmaintainedbytheUnitedStatesgovernment,GPSisfreelyaccessibletoanyonewithaGPSreceiver.Thesystemconsistsofaconstellationofatleast24satellitesorbitingtheEarth,groundcontrolstations,andmillionsofusersworldwide.GPSsatellitestransmitprecisetimingsignals,whichreceiversusetocalculatetheirexactposition(latitude,longitude,andaltitude)bymeasuringthetimeittakesforsignalstoreachthemfrommultiplesatellites.Originallycreatedformilitaryuse,GPShasbecomeessentialforcivilianapplications,includingnavigationforcars,ships,andaircraft,mapping,surveying,andlocation-basedservicesonsmartphones.Itoperatesinallweatherconditions,24hoursaday,andismaintainedbytheU.S.SpaceForce.GPShasrevolutionizedmodernnavigationandtiming,enablingcountlessindustriesandeverydayactivitiesthatrelyonprecisepositioning.Itsaccuracytypicallyrangesfromabout5to10metersforcivilianuse,whilemilitaryapplicationscanachieveevengreaterprecision.
