The diagram on the right shows an example of refraction in water waves.
Based on knowledge of the properties of refraction and refractive index, a number of applications have been developed.
The refractive index of a material is the most important property of any optical system that uses the property of refraction.
Refraction is also responsible for rainbows and for the splitting of white light into a rainbow-spectrum as it passes through a glass prism.
Other types of waves also undergo refraction, for example, when sound waves pass from one medium into another.
The most common example is the refraction of light, as happens in the formation of rainbows in the sky or rainbow-like bands when white light passes through a glass prism.
Refraction is the change in direction of a wave due to a change in its speed, as observed when a wave passes from one medium to another.