Topic: - Main Division of surveying (a) Plane Surveying (b) Geodetic Surveying Duration :- 10:46 Minutes By :- Munesh Sir Contact no :- +91 9968570131 Divisions of Surveying. The approximate shape of the earth can best be defined as an oblate tri-axial Vocaloid. But, most of the civil engineering works, concern only with a small portion of the earth which seems to be a plane surface. Plane surveys are the most commonly practised method of surveying and treat the earth as a flat or "plane" surface. Good enough for small-scale surveys in limited areas, the curvature of the earth has no effect on the results, thus the computations and results can be referenced to a plane or flat surface. Geodetic surveying is the survey in which the curvature of the earth is taken into account and the 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.