Geodesy is one of the oldest sciences. It started with establishing a location on earth through stellar navigation, and presently it is used for the same pupose with GPS.

One of the celebrated reports on geodetic activity is the one where Eratostenes of Alexandria calculated the radius of the earth about 300 B.C. This feat was done with camels and obelisks.

One of the important authors in Geodesy is G. Bomford, who published "Geodesy" in 1952 (Oxford University Press, London). This book has been out of print for a long time, but it is still a great source of information.

G. Bomford writes that "the literal meaning of 'Geodesy' is 'dividing the earth', and its first object is to provide an accurate framework for the control of topographical surveys'. As such, geodesy deals with the establishment of control for planimetric and vertical surveys, including aerial and satellite mapping.

Geodesy includes notions on how to establish accurate positions on earth and mean sea level elevations. It uses tools such as gravimeters, spirit levels, satellites, precise laser range finders, and even astronomic tools. All discussions on "ellipsoids", "projections" and "datums" belong to it. It even goes so far to provide the foundation for "Modified State Plane" procedures.