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I have been reading a book about the Computer's Processor. And I came across some of the terms like clock Ticks, clock Cycle and clock Speed that I am finding very difficult to understand. I will be very thankful if someone can clarify this in a simple language.

Peter Cordes
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    Ticks bite. Don't use that word. Clocks do cycle. A Clock Cycle is the amount of picoseconds passed between pulses of a Clock Signal (amount of millimeters a packet of photons propagated). Plus, one can make the cycle 2 times shorter, detecting both rises and falls of the signal. Also, there are multipliers, and so on. – Brian Cannard Feb 25 '19 at 19:27

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The speed of a computer processor, or CPU, is determined by the Clock Cycle, which is the amount of time between two pulses of an oscillator. Generally speaking, the higher number of pulses per second, the faster the computer processor will be able to process information. The clock speed is measured in Hz, typically either megahertz (MHz) or gigahertz (GHz). For example, a 4GHz processor performs 4,000,000,000 clock cycles per second. Computer processors can execute one or more instructions per clock cycle, depending on the type of processor. Early computer processors and slower processors can only execute one instruction per clock cycle, but faster, more advanced processors can execute multiple instructions per clock cycle, processing data more efficiently.

And on other hand, Clock Speed (Sometimes called as Clock Rate) refers to the number of pulses per second generated by an oscillator that sets the tempo for the processor. Clock speed is usually measured in MHz (megahertz, or millions of pulses per second) or GHz (gigahertz, or billions of pulses per second). Today's personal computers run at a clock speed in the hundreds of megahertz and some exceed one gigahertz. The clock speed is determined by a quartz-crystal circuit, similar to those used in radio communications equipment.

Community
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    Thanks for your help.Well I was searching for more about Clock Cycle. Can you make me more clear about the clock cycle in detail please. ? –  Apr 28 '17 at 07:19
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    Hz is 1/s. So You can translate the length of a clock cycle to some time. I'm not sure if you're shooting for this. – stephanmg Dec 01 '18 at 18:37
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    Just in case anyone else is confused by this like I was, paragraph 1 highlights Clock cycle, but then spends most of the explanation talking about clock speed. I would think Clock Cycle would be the inverse of clock speed (period vs frequency) and would be measured in nanoseconds or whatever. – xdhmoore Sep 06 '21 at 21:45
  • @xdhmoore: That's correct, a cycle is a length of time, not a rate. The frequency is the rate. e.g. a 1 GHz CPU has a cycle time of 1 ns. OTOH, very often we use "cycles" as the base unit of measurement, like "`addsd` latency is 4 cycles". Because it's always 4 cycles on a given microarchitecture like Sylake, whether it's running at 800 MHz idle or 4.2 GHz max turbo. e.g. https://uops.info/ has instruction timing info exclusively in cycles. (Plus some raw data in *reference* cycles, i.e. RDTSC ticks, which are fixed duration independent of the current core clock frequency.) – Peter Cordes Jul 10 '22 at 21:22
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A clock cycle is a single period of an oscillating clock signal.

Clock speed, rate, and frequency are used to describe the same thing: the number of clock cycles per second, measured in Hertz (Hz).

Confusingly, clock speed may also refer to clock cycle time, which is the length of a clock cycle, or the length of time between clock ticks.

Piano Telope
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