**Polar coordinates** are an alternative way of representing points on the coordinate plane. Under the standard system, a point is represented as an ordered pair (x, y) of coordinates for distance 'x' along the horizontal axis and distance 'y' along the vertical axis from a fixed point, called the origin. Under the polar coordinate system, a point is represented as an angle from the origin and a distance 'r' extended in that direction. Thus, a point under rectangular coordinates can be transformed to polar coordinates using the following rule: