When a stone is thrown on the surface of a calm lake, we see circular rings form and spread out from the drop point. These circular rings observed on the water surface are an example of wave motion. Wave motion is a disturbance that propagates from a state of rest or equilibrium without bulk motion of matter. Traveling waves can be divided into transverse waves and longitudinal waves. In a longitudinal wave, the particles of the propagating medium displace parallel to the wave propagation in back and forth motion. Sound waves traveling in air or the sound waves traveling in water are examples of longitudinal waves. Whereas, in a transverse wave, the particle displacement is perpendicular to the direction of wave propagation. Ripples on the surface of the water and the waves produced from the stretched string of a guitar are examples of transverse waves.