Dispersion is the phenomena of splitting of white light into seven colors.

The band of colored components of seven colors is known as spectrum.

As light ray travels through glass prism, different colors of light bend at different angles to the incident ray. The violet light bends the most and the red light bends at least angle. The rays of prism bends along different paths and becomes distinct.

The ray diagram showing dispersion of colors through a prism can be shown as follows: