Just to add to the previous comments: noise is a mixture of a lot of different frequencies (pitches) at a lot of different amplitudes (loudnesses), in a random, non-regularly repeating fashion.
White noise is like white light: all the “colors” (different wave frequencies) at more or less the same amplitudes.
Pink noise is like white noise, in that it has a lot of different frequencies at different amplitudes, but rather than all frequencies being equally loud, red noise is emphasized. “Red” is the lower end of the visible light spectrum—think “infrared”, which are the wavelengths below red that we can’t see (compare to ultraviolet). So when you mix “all frequencies the same” with “lower frequencies emphasized” you get pink noise. This is why pink noise sounds like it is lower in pitch than white noise.
White noise – Equal energy in each frequency. The amplitude of all sound waves are the same regardless of frequency which results in higher octaves containing more energy
Pink noise – Equal energy in each octave which results in the amplitude of the sound wave decreasing as the frequency increases.
There is also Grey noise which has equal loudness(as perceived by humans) at each frequency and Red Noise which has the amplitude fall off with the frequency squared so higher frequencies have much lower energy than in pink noise.
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