The device that separates white light into different colors is called a prism.

Here's how it works:

* Refraction: When light passes from one medium (like air) to another (like glass), it bends. This bending is called refraction.

* Different Colors, Different Speeds: Different colors of light travel at slightly different speeds within a medium like glass.

* Separation: Because of this difference in speed, each color of light bends at a slightly different angle as it enters and exits the prism. This causes the white light to spread out into a spectrum of colors, with red bending the least and violet the most.