Polar Coordinares

The polar coordinate system is a two-dimensional coordinate system in which each point on a plane is determined by a distance from a fixed point and an angle from a fixed direction. The fixed point is called the pole, and the ray from the pole in the fixed direction is the polar axis. The distance from the pole is called the radical coordinate or radius, and the angle is the angular coordinate, polar angle, or azimuth. When feta is bigger than zero than it's counterclockwise and if feta is less than zero than it's clockwise. Polar coordinates are written as (r, feta).