In a geometric plane, the coordinate system in which a point

*P*is identified using the coordinates of an ordered pair (*r*,*θ*), where*r*is the distance from the origin to the point*P*and*θ*is the angle of rotation.In a polar coordinate system, the coordinates (

*r*,*θ*) of a point*P*are called the**radial coordinate**and the**angular coordinate**, respectively, of*P*.