White is not a colour neither.
White is a light.
You cant split up White, but you can split up Light.
so we call I.E Sunlight, or light from a bulb, White light.
U get a rainbow for example, if white light hits raindrops.
raindrops act like tiny prisms that split up the sunlgith, and create a rainbow.
Since we call sunlight or bulb light white light, u prob wondering, what kind of lights we got more then?
well, a laser.
a laser is a special source of light of only one pure color
(or WAVELENGTH). (mostly Red)
You can't break up laser light into other colors.