Editing Clock rate (section)

{{Short description|Frequency at which a CPU chip or core is operating}}
{{Redirect|Clocking|the practice of tampering with odometers to read less mileage|Odometer fraud}}
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<!-- [[File:Microprocessor clock speed, OWID.svg|thumb|Microprocessor clock speed over time]] -->
[[File:CPU_clock_speed_and_Core_count_Graph.png|thumb|upright=1.8|Microprocessor clock speed measures the number of pulses per second generated by an oscillator that sets the tempo for the processor. It is measured in hertz (pulses per second).]]

'''Clock rate''' or '''clock speed''' in [[computing]] typically refers to the [[frequency]] at which the [[clock generator]] of a [[Microprocessor|processor]] can generate [[Clock signal|pulses]] used to [[Synchronization (computer science)|synchronize]] the operations of its components.<ref>{{FOLDOC|new=yes|Clock}}</ref> It is  used as an indicator of the processor's speed. Clock rate is measured in the [[International System of Units|SI]] unit of frequency [[hertz]] (Hz).

The clock rate of the first generation of computers was measured in hertz or kilohertz (kHz), the first [[personal computer]]s from the 1970s through the 1980s had clock rates measured in megahertz (MHz). In the 21st century the speed of modern [[Central processing unit|CPU]]s is commonly advertised in gigahertz (GHz). This metric is most useful when comparing processors within the same family, holding constant other features that may affect [[Computer performance|performance]].