Caption: An animation of how a prism disperses white light into a continuous spectrum.

Actually, the prism disperses some infrared and ultraviolet light, but the human eye doesn't notice that.

In many scientific applications, greater and better dispersion is obtained using a diffraction grating rather than a prism.

A compact disc is incidentally acts as a crude diffraction grating. That is NOT its function, but it disperses light rather prettily.

Credit/Permission: Lucas V. Barbosa (AKA User:LucasVB), 2007 / Public domain.
Image link: Wikipedia: File:Light dispersion conceptual waves.gif.
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File: Optics file: prism_animation.html.