Glossary: Frequency

The term frequency refers to a number of recurring events, such as a "sine wave," representing the alternating voltage or Frames per unit time, usually per second. The unit of frequency in Hertz (Hz = 1/sec), named after the German physicist Heinrich Rudolf Hertz.

The human ear perceives frequencies from 20 Hz to about 20000 Hz. The frequency of a standard Pitch is 440 Hz for example.