Hint: Dispersion is the phenomenon by which white light is split into different colours of the visible spectrum of electromagnetic energy. The colours of this light in the proper sequence include the various colours in a rainbow where the visible light is naturally split into its different colours by droplets of water falling in the rain.
Complete Step by step solution: Dispersion is the phenomenon by which white light splits into various colours of visible light due to the electromagnetic waves’ dependence of phase velocity on its frequency. The electromagnetic waves of the visible spectrum when combined form a white light which has all the wavelengths of the visible light. When these spectra of various wavelengths pass through a prism, then due to the dependence of the refractive index on the frequency of the spectra, the waves split into various bands of visible light since they are made to refract at various angles. This causes the white light to be able to be seen as a combination of various waves of the electromagnetic spectrum.
Light as we know is an electromagnetic wave. The colours which are produced by visible light are called pure spectral colours and there is no clear boundary between one colour and the next. The different colours of light in the proper sequence in the spectrum of light are Violet, Indigo, Blue, Green, Yellow, Orange, and Red.
Note: The entire electromagnetic spectrum in increasing frequency consists of radio waves, microwaves, infra-red rays, visible light, ultra-violet rays, X-rays, and $\gamma $-rays. These are continuous and there is no specific boundary between them although they are further classified into various classes.