Humans have three types of cone cells in their eyes. This trio of photoreceptors typically detects red, green and blue wavelengths of light, which combine into millions of distinct colors in the spectrum from 380 to 700 nanometers in wavelength- what we call visible light.
A lot of times, the change of color is the important or interesting part of a signal.
[
add
]
[
|
|
...
]