How do we Identify Circular And Periodic Motion?

Circular motion is almost always a repetitive movement. Circular motion is where the object goes along a circular direction-can be a complete circle, can be a part of the circle. Periodic motion is where, for a given moment, the object continues its motion. Consequently, when an object passes through a circle uniformly and completes 360 degrees, it repeats itself. Therefore it is a periodic motion.
 

Likewise in the case of a single pendulum. In a part of a circle, the pendulum oscillates then continues its motion after its time span. A fan spinning is circular as well as periodic