Signal to Noise Ratio

Signal to noise ratio, sometimes expressed as SNR or S/N, refers to the ratio of the nominal signal level to the undesired noise level. This stretches from just above your noise floor, right up to your nominal signal level. How large your signal to noise ratio is depends on what equipment you are using, your acoustic environment and also the bit depth that you use to record at.

Diagram explaining noise floor and signal to noise ratio