Geodetic surveying is the survey in which the curvature of the earth is taken into account and higher degree of accuracy in linear and angular observations is achieved. The geodetic surveys extend over large areas and lines connecting any two points on the surface of the earth are treated as arcs.
For calculating their projected distances on the plans or maps, the correction for the earth’s curvature is applied to the measured distances. The angles between the curved lines are treated as spherical angles. A knowledge of spherical trigonometry is necessary for making measurements for the geodetic surveys.