[[Image:GPS Satellite NASA art-iif.jpg|right|thumb|Artist's conception of GPS Block II-F satellite in orbit]]
The '''analysis of errors incomputed using the information[[Global reported by thePositioning System|Global Positioning System]]''',ais space-basedimportant satellitefor systemunderstanding forhow navigationGPS works, isand importantfor toknowing estimatingwhat themagnitude accuracyerrors ofshould positionbe estimatesexpected. andcorrectingThe Global Positioning System makes corrections for thereceiver clock errors and other effects but there are still residual errors which are not corrected. The Global Positioning System (GPS) was created by the United States Department of Defense (DOD) in the 1970s. It has come to be widely used for navigation both by the U.S. military and the general public.
User vehicle position is computed by the receiver based on data received from the satellites. Errors depend on geometric dilution of position and the sources listed in the table below.
The positioning data provided directly by the satellites is extremely precise but there are many factors that can make the errors in the data non-trivial. In situations where high accuracy is necessary, understanding and compensating for these sources of error is important. Sources of error include atmospheric distortion (predominantly in the [[ionosphere]]), satellite clock inaccuracies, and the travel delays of the satellite signals.
