Our eyes react to different shades of light, and what we determine as colors are different wavelengths of light. When we say an object is a certain color, it is because it is reflecting more of a certain wavelength light. For example red objects reflect "red" light, or light with a longer wavelength (lower frequency) better than other types of light. Dark objects tend not to reflect light very well at all, even if it reflects one color better than the other. White objects, tend to reflect all types of light equally well, and tend to reflect most of the light cast on it.

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