The effect of a sharply applied, localized disturbance in a medium soon transmits or spreads to other parts of the medium. This simple fact forms a basis for study of the fascinating subject known as wave propagation. The manifestation of this phenomenon are familiar to everyone in forms such as the transmission of sound in air, the spreading of ripples on a pond of water, the transmission of seismic tremors in the earth or the transmission of radio waves. The propagation of disturbances in the various media like gas, liquid as we will as solid share many common features, therefore that a person versed in the science of one understands much about the others. The physical basis for the propagation of a disturbance ultimately lies in the interaction of the discrete atoms of the medium. Investigations along such lines are more tunes to Physics than mechanics, except. In solid as we will as fluid mechanics, the medium is regarded as continuous, therefore that properties such as density or elastic constants are considered to be continuous functions representing averages of microscopic quantities.