|Assume that you are replacing the
bearings in the wheel of your bicycle. To test if you have done a
good job, you hold the axle vertically and give it a spin. The axle
at the center of the wheel is stationary. The wheel as a whole has
no translational motion. But
the wheel is turning around the axle. Every point on the wheel
undergoes circular motion about an axis of rotation. Such motion
around an axis of rotation is called
Extended object can have translational and rotational motion. Any motion of an extended object can be viewed as a combination of translational motion of the center of mass and rotational motion about the center of mass.
A foam square has a blue LED near its CM and a red LED near its edge. If we toss the sponge we can easily observe the parabolic motion of the CM and the rotational motion about the CM.