We’ve all heard of white noise, best known at one point for the snow on our television sets when the cable was out. It’s the most popular of all the colors of noise out there, often on sound machines to help with sleep by drowning out the deafening silence or unwanted noises.

However, according to the Science Notes website, there are other colors of noise, and they come down to frequency and amplitude.

WHITE NOISE

This contains all frequencies in equal measure that sound like a heavy waterfall or high fan to help get a nice, solid sleep.

PINK NOISE

Pink noise, like ocean waves or steady rain without thunder and wind, is softer in high-frequency tones and stronger in low-frequency tones than white noise. According to The Sleep Foundation, it calms the brain and improves memory.

BROWN NOISE

According to the Sound of Sleep website, brown noise, like a roaring river or heavy ocean surf, has a much higher base and intensity than white noise. It improves focus, relaxation, and sleep.

GREEN NOISE

According to the Sleep Foundation, this is less studied right now; however, this sound, which is very similar to white noise, just at a slightly lower level, may help people who have racing thoughts and anxiety as well as sleep.

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Whether you like sound machines and different colors of noise or not, our brains and bodies will always react to sound.