WHAT IS WHITE NOICE? EXPLANATION.

The best way to explain White Noise is to first look at why it has been given that name. White is used because of the way light works. White light is not an absence of color but is rather a combination of ALL colors. Going along with that same reasoning, White Noise is a combination of ALL frequencies of sound all playing at the same time.
Because white noise is actually a combination of all frequencies it is most likely used as a sound blocker. It is typically used by those in loud city environments or with exceptionally noisy neighbors.
Think of it this way. If you are having a conversation with one person in an empty room you would have no problem understanding that person. Now imagine you are at Sunday family dinner and instead of that one person there are now 20 people around the table all talking at the some time. You would struggle to hear them all so you only pick up one or two voices. Now multiply that times 1,000. Suddenly you have a sea of people all talking at the same time and it is impossible for your brain to “hear" any single voice. Now imagine your noisy neighbor is one of those people. Suddenly you can’t hear them, instead all your brain “hears" is a gentle wave of sound.
When those voices are now frequencies, you get a sound that is a bit like static of a radio.