Whats white noise that comes from a sleep machine?

Question

i understand that a sleep machine has " white noise" but i wuz just wondering what white noise is? thanks

Answer 1

White noise contains all frequencies of sound at an equal level.  The closest thing you have probably experienced in life is the noise from an FM radio when it is tuned between stations.

The sleep machines often advertise white noise but actually produce "pink noise".  Similar concept, but pink noise contains equal levels of energy per octave.  The difference is technical, the result is a less harsh sound that is more soothing.