Surveying : Basic Introduction

SURVEYING:

Surveying is defined as the process of determining the relative positions of points on the earth. The points may be on the earth surface, above the earth and beneath the earth
Relative positions means w.r.t to a fixed direction or by selecting a random direction
In India the reference is MSL of Mumbai
Diameter of polar axis is 12713.8 km and diameter of Equatorial axis is 2756.75 km
So avg dia of earth is 12742 km and avg radius is 6370 km
So we can say the Equatorial axis is 42.95 km larger then polar axis
Shape of earth is oblate spheroid

To prepare maps and plans
Calculate area and volume
To set-out a proposed civil engineering work ( the process of putting the plan on the ground is called setting out)