What is a CPU used for?

CPU - Central Processing Unit / main processor

CPU stands for Central Processing Unit. This is the central processing unit in a computer. This is the main processor, also simply called the processor.

The main processor is the functional unit in a computer that provides the actual processing power. He is responsible for the information processing and the control of the processing sequences. To do this, the main processor fetches the commands one after the other from the memory and initiates the information processing.
In addition to the main processor, there are other processors that relieve the main processor of certain calculations. The graphics processor (GPU) is responsible for graphic calculations, for example.

The main processor, or CPU, is the heart of any electronic device that does computer-like tasks. It is used in smartphones, pocket calculators and in computers for which it was actually invented.

The most famous processors come from Intel, AMD and ARM. These companies play a leading role in the development and manufacture of processors. This mainly applies to servers, desktop PCs and notebooks. But there are many other manufacturers and developers of processors. In the area of ​​smartphones, tablets and household appliances, Intel and AMD do not play a role. There are special processors from other manufacturers.

GPU - Graphic Processing Unit (graphics processor)

The graphics processor (GPU) is responsible for graphic calculations. It supports the main processor (CPU), which supplies the actual raw data for the graphic output. The graphics processor then makes the raw data pretty. For example, the graphics processor takes care of 3D effects and the covering of surfaces with textures or patterns.
The graphics processor is either integrated into the CPU, onboard on the motherboard or on a graphics card that can be used to expand a computer.


The microprocessor is a processor that is completely incorporated into a single circuit. The processor in a personal computer is typically such a microprocessor.


A microcontroller is a processor that has additional analog and digital inputs and outputs and is intended for control tasks. It is already seen as a complete computer classified in the embedded field.

Why a processor cannot calculate!

When calculating with binary numbers, the same rules apply in principle as with decimal numbers. The problem, however, is that binary numbers have no signs or decimal places and, for example, there is no logical link for subtraction.
Calculating with binary numbers, and that is the job of a processor, is not that simple and therefore very cumbersome. Calculating with numbers that are not positive and integer requires complicated functions that have to be assembled in a processor with logical functions.

Overview: processor technology

For a long time, developments in processor technology followed an apparently simple law. The internal structure was optimized, the structures made smaller, the operating voltage lowered, the clock frequency increased or the manufacturing process improved. The next generation of processors was born. However, there are narrow physical limits to this development.

It's about the question of how you can make a processor even more powerful.

In order to increase the performance of processors, some function blocks are integrated several times. These work in parallel and thus increase the computing speed of the processor.
Due to the large number of functionalities, the CPU manufacturers try to design their processors in a modular manner. In this way, the individual circuit parts can be better developed. It also helps to save power if individual processor parts can be switched off. In addition, different variants can be combined and new processor types can be built.
In addition to the chipset, the memory controller and graphics output are now an integral part of every desktop processor.

CPU architectures

The x86 technology from AMD and Intel, at least their processors, are also known to the general public. ARM-based CPUs, on the other hand, are significantly fewer. Most CPU architectures are only known to experts. The many unknown CPUs are often in devices of daily use. ARM CPUs are in practically every smartphone and tablet. A MIPS chip is in every Fritzbox, an AVR core in the Arduino and an Xtensa LX6 in the ESP32.

  • x86 technology from AMD and Intel
  • POOR
  • PowerPC
  • MIPS
  • ARC
  • AVR
  • XTensa
  • OpenRISC
  • Open-SPARC
  • OpenPOWER
  • RISC-V

Processor socket

In the early days of computers, processors, as is common with semiconductors, were firmly soldered to the motherboard. At some point they met the need to sell the processor and motherboard products separately. Since the 486 (processor from Intel) it has been common to attach a socket to the motherboard instead of a processor. Only when the computer is assembled is the processor inserted into the socket and attached to the motherboard together with the heat sink and fan.
The processor manufacturers are responsible for the processor socket, but they work together with the chipset and motherboard manufacturers at this point.
Since a new processor socket comes with every new processor generation, newer processors no longer fit into older motherboards.

Processor manufacturer

Other related topics:

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