Angular motion is the rotatory movement of an object or body about a real or imaginary axis of rotation. It is usually expressed in degrees where a complete circle is 360 degrees. However, due to the large number of degrees moved, it is often expressed in radians. One radian is equal to approximately 57.3 degrees and there are 2π radians in one circle. Within angular motion the terms scalar and vector quantities apply, but it is often more desirable to use clockwise and anti-clockwise rotation. In order to perform effective and efficient movement such as kicking a ball, a recognition of the importance of angular motion is essential.