If a point in a rigid body is not fixed, it can possess rotational motion as well as translational motion. The general motion of a rigid body consists of both these motions. For example, the motion of an automobile wheel on a plane horizontal surface.
The kinetic energy of translation is
(KE)tr = ½Mvcm2
The kinetic energy of rotation is
(KE)rot = ½Iω2
The total energy of the body due to translation and rotation is the sum of these two kinetic energies.