What is the function of a clock for a cpu?

Clock in CPU(central processing unit) is the indication device that describes about the processing of the instruction in a computer.

Explanation: Clock rate in the CPU gives the knowledge about the instruction processing in the computer is fast , slow or moderate.The higher rate of clock cycle , the better execution of instruction in the CPU. The rate or cycle of clock is measured in terms of megahertz(MHz) or   gigahertz(GHz). The range of the clock speed ranges from 3.5 GHz to GHz, which is considered as normal speed for the execution of instruction.  

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