White light is made up of three colours, blue, red and green. These three colours are known as primary colours. The three colours are blended with each other and you get to see a white light. All colours of the universe have different wavelengths. When these waves come together and are seen together, you get to see a white light. The colour red has the longest wavelength while the colour purple has the shortest wavelength. When you look at the colours of the rainbow from a side angle, you will see a white light. The reason we see so many colours of the rainbow is because the white light breaks into different wavelengths which produces many colours.
