From a technical point of view, the definition sounds like this:
Clock frequency is the number of cycles produced in a given amount of time.
For me, it was also a dark forest, when in my first year I wrote this in a notebook, studying to be a programmer. Then I, like many now, did not understand at all what this meant and why it was needed?
I will explain with examples, it will be easier to understand how it works. Let's start.
Explanation with an example
Let's imagine that 1 hit on the musical drum is 1 cycle of the processor. We take two drums for comparison, one is struck 120 times per minute, the second is struck 80 times per minute, it will be obvious that the frequency of the sound of the first drum is higher and louder than that of the second.
For an independent experiment, you can take an ordinary writing pen in your hand, detect 10 seconds and make 10 hits with the edge of the pen on the table, and then make 20 hits in the same time, the result will be the same as with the drums. 
You also need to understand that if a musician has four drums, instead of one, then the number of beats will not be multiplied by the number of drums, but distributed to everything, thereby there will be more opportunities in playing sounds.
Remember! The number of cores is not multiplied by gigahertz.
And that is why, nowhere in the descriptions are there such large numbers as 12Ghz or 24GHz, well, etc., if only in the results of overclocking, and then hardly. 
In a microprocessor, a certain number of instructions are executed per cycle. That is, the higher the clock frequency, the more commands executed in a certain amount of time occur inside the microprocessor.
By the way, you can find out about what's inside in the article - "", which has already appeared on the blog. Further more interesting, so to always be aware of new articles.
What is measured and how is it indicated
In gigahertz or megahertz, abbreviated as - GHz or MHz, Ghz or Mhz.
3.2 Ghz = 3200 Mhz is the same thing, only in different values.
On sites, in the description, the frequency is indicated in different ways. Examples are shown below and highlighted in blue. 
Influence in work and play
When working at a computer, this parameter affects:
- system performance
- responsiveness and speed
- computing power
- running multiple running tasks at the same time
- and many others.
How does it affect games? It directly depends on how much power is needed for the game. Manufacturers recommend using 3.0GHz or higher. It all depends on the game itself and the recommendations that come with it. Where to watch them? You can read in which I told everything in detail.
One of the CPU models that has the highest clock speed at the time of writing is the Intel i7-8700K. 
Many of course believe that this parameter is not the most important, but this indicator directly affects the performance of the PC, so if you have the opportunity to purchase a higher gigahertz, I advise you to consider it.
In my opinion, I would consider these optimal models for various tasks:
- Intel Pentium G5600
- AMD Ryzen 3 2200G
- Intel Core i3 8100
- Intel Core i5 8400
- Intel Core i7 8700
What tasks are they intended for? You can see in the article how, so as not to regret later.
I don't list prices as they change all the time, so check it out. The choice is yours.
I hope everything became clear to you. I will end with this. To stay up to date on the appearance of new, understandable and interesting articles on my blog, leave comments, I'm always interested in your opinion. Thank you for your attention. See you in new articles.
Clock frequency called a parameter that is measured in gigahertz. A higher such frequency allows faster processing of data. This is one of the most important parameters that you should pay attention to when choosing a processor.
No less important is the number of cores, the fact is that the clock frequency at this stage of development can no longer be increased, this prompted to continue development in the direction of parallel computing, which is expressed in an increase in the number of cores. The number of cores informs about how many programs can be run simultaneously without losing performance. However, it should be borne in mind that if the program is optimized for two cores, then even with more of them, the computer will not be able to fully use them.
Cache and processor bus frequency
The bus frequency indicates the rate at which information is transmitted to and from the processor. The larger this indicator, the faster the exchange of information occurs, gigahertz are used as units of measurement here. Of great importance is the processor cache, which is a high-speed block of memory. It is located directly on the core and serves to improve performance, since data is processed at a much higher speed in it than in the case of RAM. There are three levels of cache memory:
L1 - the first level is the smallest in volume, but the fastest, its size varies between 8 - 128 KB.
L2 - the second level, much slower than the first, but exceeds it in volume, here the size varies between 128 - 12288 KB.
L3 - the third level, loses in speed to the first two levels, but the most voluminous one, by the way, it may be completely absent, as it is provided for special editions of processors or server solutions. Its size reaches 16384 KB, it can be present in such processors as Xeon MP, Pentium 4 Extreme Edition or Itanium 2.
Socket and heat dissipation
Less significant, but still relevant when choosing a processor, are characteristics such as socket and heat dissipation. socket This is the socket where the processor is installed on the motherboard. By indicators heat dissipation you can determine the degree of heating of the processor during operation. This indicator is measured in watts, and it varies between 10 - 165W.
The average cost of processors in the Moscow market of Intel Core 2 Duo is 5000 rubles, and AMD Athlon X2 Dual-Core RUR 3000, according to http://price.ru
Tab. 3 Comparison of processors
For graphics, the bus and processor frequencies are important, therefore, in accordance with the minimum hardware requirements when choosing between the two proposed CPUs, based on the above key characteristics, as well as price qualities, I prefer the AMD ATHLON II X2 CPU http://www.nix.ru .
