What is "White Noise"?

"White Noise" resembles the background sounds of the womb. In that environment, all sounds are dominated by the mother’s heartbeat, her breathing and amniotic fluid circulation and are thus partly distorted for the baby. Even if the mother is in a quiet environment, the baby never is in silence in her womb.
White noise is a sound mixture which contains every frequency in the range of human hearing, in equal proportions. In other words, it is a mix of sounds, which includes high and low tones and every sound in between. The combination of different tones causes most other tones to be lost. Our brain has trouble distinguishing through the continuous sounding of all these frequencies, and thus the background noises are much less distinguished. The TV or radio static, as well as a washing machine, vacuum cleaner, fan or running water sounds can all be considered white noise and facilitate sleep for both babies and adults.