Hertz

From Overclocking Wiki

Hertz is the unit specified by the International System of Units to measure frequency—the number of times a repeated event will occur over a period of time.

Hertz uses a second as the base unit of time. A signal of 10 Hertz cycles ten times per second.

Computer clock speeds are measured in Hertz.

Hertz is abbreviated "Hz". Other SI multipliers may be added to the unit, such as "gigahertz" for billions of times per second.