It is a kind of disturbance which travels through a medium due to the repeated vibrations of the particles of the medium about their mean positions, the disturbance being handed over from one particle to the next. In a wave both information and energy propagate from one point to another but there is no motion of matter as a whole through medium.
Three types of waves:
(i) Mechanical waves: The waves which requires a mechanical medium for their propagation are called mechanical waves or elastic waves. For their propagation, the medium must possess the properties of inertia and elasticity. For example, water waves, sound waves, etc.
(ii) Electromagnetic waves: The waves which travel n in the form of oscillating electric and magnetic fields are called electromagnetic waves. Such waves do not require any material medium for their propagation. For example, visible light, radio waves, etc.
(iii) Matter waves: The waves associated with microscopic particles, such as electrons, protons, neutrons, atoms, molecules, etc.
