Signal-to-noise ratio

Imagine you have a toy with a sound button. When you press the button, the toy makes a noise, but sometimes there's a lot of other noises around you that make it harder to hear the toy noise.

The noise that you really want to hear is called the signal, and all the other noises around you are called the noise.

The signal-to-noise ratio tells us about the strength of the signal compared to the noise. If there's a lot of noise, then the signal-to-noise ratio is low, because the noise is stronger than the signal.

But if there's not as much noise, then the signal-to-noise ratio is high, because the signal comes out more clearly than the noise.

In other words, the more clear and strong the signal is compared to the noise, the higher the signal-to-noise ratio, and the easier it is for us to understand and hear the signal.