CPU also was known as processor stands for central processing unit. This is what does the calculations In your computer and is most probably the main contributor to the speed and responsiveness 
This is what does the calculations In your computer and is most probably the main contributor to the speed and responsiveness.
For example, The speed or clock frequency refers to how many cycles the processor goes through in a second.
A 3.0 GHz processor does 3 million (billion!) cycles per second. Obviously the more cycles the faster the unit, however, the efficiency of each cycle is also important.
The efficiency of each cycle is known as IPC, instruction per cycle.
Just to visualize this a bit, imagine a man running. You’re trying to get from point A to point B. The faster you run the faster you get there. However, if you have a small stride then for every leg movement you don’t cover much land. In the same way, a CPU despite having a fast clock frequency must also have a large IPC to be effective. Another concept of the processor is the cache.The cache is simply ultra-fast accessible memory in the processor. 
The cache stores data temporarily which may be required from the CPU. If the CPU had to get data from the RAM modules, it would take time so most CPU’s have the cache which will store data which can be sent fast to the CPU when it needs it. The bigger the cache the faster the CPU will be at performing tasks. There are also cores, you may have heard dual core, quad core and even hex core. Basically the more cores, the easier the CPU can deal with the data it is fed. Now if you don’t understand this, I don’t blame you, I will try and visualize it. Imagine a river. The river is your processor. Information is chucked at one end of your river.
The cache ensures that Information is chucked in quickly. The Information is data which needs to be processed. The rivers primary aim is to get rid of the Information or process the information. The speed the river flows is the clock speed, the faster the river flows the faster the Information will pass. The instruction per cycle is the effectiveness of each ripple. Cores are when the river splits into channels. It makes the river be able to easily distribute the Information. So the information passed through, the fast speed of the river meant that the data was processed fast and the multiple cores meant that the processor could do its tasks much more efficiently. The cache meant that the Information could quickly be put in one end of the river.
