The number of pulses per second generated by an oscillator that sets the tempo for the processor is known as clock speed. the clock speed is measured in MHZ & GHz. the speed of microprocessor depends on various factors such as the number of instructions its process, bandwidth and the club Speed. the bandwidth specifies the number of binary digits that the microprocessor can process in a single instruction. the clock speed of the microprocessor is from 66 mhz to 3.8 GHz. the speed of microprocessor also depends on the number of the transistors built into the processor.