Angular frequency represents how quickly an object completes one full revolution or cycle in radians per unit of time.
Periodic motion: Periodic motion refers to any motion that repeats itself after a certain interval of time.
SHM is a type of periodic motion where the restoring force acting on an object is directly proportional to its displacement from equilibrium.
Oscillation: Oscillation refers to repetitive back-and-forth movement around an equilibrium position.