This significant accuracy update resulted in WGS84, the current geodetic standard. The deployment of the GPS constellation allowed the surveying process to be updated in 1984 incorporating GPS as the primary method of reference. WGS development and refinement continued through this time period during which new satellite, surface gravity and astrogeodetic data, from both military and non-military sources, were used to develop WGS72. the committee's efforts resulting in WGS66 which was implemented in 1967 and served the Department of Defense needs for about five years. In 1966, a tri-service World Geodetic System Committee was assigned the responsibility of developing an improved WGS, based on newly available satellite imagery, surface gravity observations and doppler data, to satisfy evolving mapping, charting and navigation requirements. Efforts of the Army, Navy and Air Force were combined and lead to the development of the DoD World Geodetic System 1960 (WGS60). In the late 1950’s, the US Department of Defense began to develop a worldwide system, referenced to geodetic datums, which was intended to establish compatibility between the coordinates of widely separated locations. The current ICAO standard World Geodetic System is WGS84. It comprises a standard coordinate frame for the Earth, and a gravitational equipotential surface (the geoid) that defines the nominal sea level. The World Geodetic System is a standard for use in cartography, and in navigation. One or more locations on the Earth's surface are chosen as anchor "base-points". Each datum starts with an ellipsoid (stretched sphere), and then defines latitude, longitude and altitude coordinates.
Datums are used in geodesy (the branch of mathematics dealing with the shape and area of the earth), navigation, cartography and by Global Navigation Satellite Systems (GNSS), such as the Global Positioning System (GPS) and the Global Orbiting Navigation System (GLONASS). A geodetic datum or geodetic system is a coordinate system, and a set of reference points, used for locating places on the Earth.
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