Sampling rates are measured in hertz (Hz) or cycles per second. This value represents the number of samples captured in order to represent the waveform. The more samples you take per second, the higher the sound quality. The human ear can hear sounds that fall approximately between 20 Hz and 20,000 Hz.
Capturing a sound at a particular frequency requires a sampling rate of at least twice that frequency. This frequency is known as the Nyquist frequency. If you want to capture sound within the range of human hearing, the sampling rate has to be at least 40,000 Hz. Capturing sound at higher rates than this is known as over-sampling. Aliasing occurs when a signal is sampled at sampled at less than twice the highest frequency present in the A sampling rate of 44,100 Hz is used for audio CDs. The most common sampling rates for audio are: 8 kHz, 16 kHz, 22.05 kHz, 22.25 kHz, 44.1 kHz, 48 kHz, 96 kHz, and 192 kHz. (Audacity manual and Wake Forest University).