What is CPU?

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Every small and big computer has its CPU. You may have heard about CPUs before, but what is it truly? What is the CPU and how does it work?

In this beginner-friendly article, you’ll learn exactly what a CPU is. and I will give you an overview of all the info about that.

Definition

The Central Processing Unit (CPU) is the main part of a computing device that functions as its “brain.” It is one of the most important pieces in any model of digital computers.

Meaning

CPU stands for central processing unit which means the main headquarter of all computing processes of a computer.

History

The term CPU Central processing unit was used as early as 1955 when the first CPU was known as UNIVAC 1103 as the component of the UNIVAC 1 computer,

which was the vacuum tube-based CPU, large in size and slow in speed compared to the latest CPU.

But the first commercial CPU was invented in 1971 by Federico Faggin an Italian physicist as a component of Intel 4004.

Where do you find a CPU in a computer?

In a CPU there are thousands of microscopic transistors, these transistors are actually tiny switches that control the flow of electricity through the integrated circuits. The CPU is located on the computer’s motherboard.

What is a motherboard? The main circuit board of a computer which connects all hardware components together is known as the motherboard.

Then we will move on, So the CPU is the heart and brain of digital computers and is responsible for managing all the work. It performs every little action a computer does and executes the programs.

What are computer programs and where are they stored?

For doing everything, there is a program for the CPU.

You have a program that lets you use your media player or web browser. You have one that performs mathematical calculations on a calculator or allows you to type characters or letters etc. on a keyboard and there are programs that manage the movement of the cursor or click anything with it.

Whatever activity is it, there is always a program for doing all computer activities.

What is a program? A set of instructions that need to be executed in a logical order, sequential and be followed exactly step by step is known as Program.

These all instructions are written by a human programmer, in a human-readable programming language.

Computers don’t recognize programming languages directly, so they need to translate them into easily recognizable forms. That form is known as binary or machine language.

The base two numerical system is Binary. It consists of only two numbers: 0 and 1.

This reflects and binds in well with the only two viable states transistors have to control the ebb and flow of electric current – they are either on (1) or off (0).

So, in its internal workings, the programs are stored or saved as sequences of bits. The binary digits are also known by another name Bits, which are sequences of 1s and 0s.

Programs can be stored for a long term or permanently in a storage device, no matter whether it is an HDD (Hard disk drive) or SSD (Solid state drive). These storages are non-volatile, which means that they can store your data even when the power is off.

While a program is running and currently being used, so, it’s all data is stored in the primary memory RAM (Random access memory), which is a volatile storage. It means it will flash your all data when the power shuts down.

What does a CPU do?

A CPU is usually responsible for managing the processing of mathematical and logical operations and executing the instructions given.

CPU can execute millions of instructions per second but can fulfill only one instruction at a time.

Firstly, it takes some input, usually from an input device (like from a Monitor display screen or keyboard or mouse, etc.). or from any application or browser,

Then the CPU does four tasks.

Fetching instructions from memory, to know how to manage the input and understand the corresponding instructions for that particular input data it received. It looks for the destination of the corresponding instructions and forwards the request to the RAM. The RAM and CPU work together constantly. This process is also known as Reading from memory.
Decoding is the second task, in which it translates the instructions into a language which it can understand, which is binary language and also known as machine language.
Executing and fulfilling the instructions is 3^rd task.
Storing and saving the result of execution in the memory for later retrieval if and when requested. This is also known as writing to memory.

Finally, it gives the result in the form of some kind of output, such as printing something, etc.

The above-all process is known as the fetch-execute cycle and happens millions of times in a second.

The main parts of a CPU

Now you know about the basic tasks performed by a CPU for every operation happening on a computer. Then we will learn what are the parts of the CPU that work together to do tasks.

Below I will tell you some of the important components of the CPU:

The Control Unit (CU), is the component of CPU that fetch and retrieve the instructions and commands from the main memory and later decodes them into binary or machine language.
The Arithmetic Logic Unit (ALU), is the component of the CPU where all the processes and mathematic operations take place such as addition, subtraction, multiplication, and division. The logical operations for decision-making like comparing data are also done by it.
The Registers are the components of a CPU which are known as Extremely fast memory locations. The currently being processed instructions and data during the fetch-execute cycle are stored there for quick-to-quick access by the processor.

What are CPU cores?

You know that a CPU can perform/execute or carry out just one action at a time and it does this with the assistance of physical cores.

The core is the CPU itself, a separate component inside the main chip of the CPU. This core can do just one operation at a time. However, the latest computers can support more than one core inside the main chip.

The more cores a CPU has, the greater its computation ability, and the more operations that can be running simultaneously make the CPU a serial multitasker.

This means if a computer has dual-core CPUs then it has two CPUs on the same chip that can fulfill two instructions at a time.

If a computer has Quad-core then it has four CPUs on the same chip and can carry out the result of four instructions at a time.

Simply like that, if a computer has Hexa-core, then it has six CPUs on the same chip and can executes six operations at a time.

What is hyperthreading?

Nowadays the latest CPUs also support a technology called hyperthreading,

In this technology, the single physical core appears as multiple cores in front of the computer, the operating system thinks that it has more power but it does not actually.

So, like the physical cores, these are virtual cores also known as threads. These do not physically exist but they appear to be so.

The duo of the physical core and virtual core can make the execution time of programs better and even faster and can give the CPU more power of computation.

What is CPU?

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