Full Form of CPU: What is CPU in Computer?

CPU is a very general term in the field of computers and many other electronic devices. A computer system cannot function without the CPU, making it the key component of the computer. Although the term is quite common, most people get confused about whether there is any full form of CPU? 

In this article, we are discussing the essential topics about CPU including the CPU full form, definition, types, components used, etc. 

Quick Links [Show/ Hide List] • What is the full form of CPU? • What is a CPU? • History of CPU • Construction of CPU • Components of CPU • How does CPU work? • Types of CPU • Summary

The meaning or full form of CPU is Central Processing Unit. It is one of the primary units used on computers these days. CPU usage is also very common in other electronic devices. For example, smartphones, tablets, notebooks, gaming consoles, etc. In the context of computers, the CPU is also known by many other names such as chip, processor, central processor, main processor, processing device, etc.

The full form of CPU can be explained as:

Let’s talk about what exactly CPU is:

As the name suggests, the Central Processing Unit is the primary component of the computer that helps to perform most of the processing for the computer. It adds processing power to the computer, allowing the computer to execute a set of instructions or programs inside the computer. Modern computers come with a powerful central processing unit to process multiple tasks at once.

The CPU is responsible for processing all the basic to complex arithmetic and logical operations in the computer to accomplish the respective results. Also, it controls all the activities within the computer and helps the various components of the computer system to communicate with each other to perform their respective functions. The CPU also takes the help of chipsets or other microchips mounted on the motherboard to control the flow of data and instructions between computer parts.

Intel and AMD are currently the two most popular manufacturers of computer processors. Furthermore, Snapdragon and MediaTek are two popular manufacturers of mobile phone processors.

The use of the term CPU in the computer industry dates back to the early 1960s. Initially, the term CPU was used to refer to a device designed for software execution and this came about with the advent of the stored-program computer.

In 1971, Intel released the first commercial CPU, named the Intel 4004. Italian physicist Federico Faggin was the principal designer of the first commercial CPU and is called the inventor of the CPU. This CPU was designed and intended for use as a single-core-chip in programmable calculators. Later, there was a continuous development towards compression of the CPU structure until it was converted to a single-chip design.

Some important events related to the history of CPU are as follows:

• Silicon, one of the primary elements of CPU, was introduced by Baron Jons Jackob in the year 1823.

• In 1903, Nikola Tesla patented an electrical logic circuit (gate or switch).

• The first transistor was designed in 1947 at Bell Laboratories by John Barden, Walter Brattain, and William Shockley.

• The first integrated circuit was designed by Robert Noyce and Jack Kilby in the year 1958.

• Modern CPUs come with millions of transistors coupled on a single rectangular silicon chip.

When it comes to manufacturing, the CPU is made up of a large number of integrated circuits which are connected on a single circuitry or chip. Integrated circuits (ICs) are manufactured using millions of nano components, known as transistors, and made of semiconductor material, or silicon.

Transistors used in CPUs are commonly referred to as the building blocks for processors. They are programmed to have two specific states, such as On or Off. They can either be On or Off at a time. This is one of the main reasons why a computer’s processor understands binary code, 0 (Off state) and 1 (On state).

Although the physical structure or design may change slightly from one CPU to another, each CPU consists of the following three components: 

The control unit is the main component of the CPU and handles all computer operations and activities, such as input/output devices, memory handling, process execution sequences, etc. It can be referred to as the center of all the processing activities that take place inside a computer device, making it the backbone of the computer to some extent.

The arithmetic logic unit is another essential component of the CPU. It comes into play when any mathematical, logical, comparison based or decision-making process is to be processed. This unit handles mathematical operations like addition, subtraction, division, multiplication, and logical operations like AND, OR, equal to, less than, greater than, etc.

The memory unit of the CPU refers to the built-in memory of the CPU. It is not part of the main memory (or RAM). Instead, it is memory located in the CPU in the form of caches and registers. CPU memory is the smallest and fastest memory of the computer. CPU uses this memory to store input data, instructions, running data, and running results. Since CPU memory is small, the CPU can also use main memory to store corresponding data when needed or when the size of data is comparatively large to store.

The components of the CPU are also referred to as the ‘Functional Units’ of the computer system.

The working or functioning of the CPU can be explained by the following four operations:

• Fetch: CPU receives or takes instructions from memory unit or from RAM.

• Decode: Instructions are converted to know which other parts of the computer should be used to process a particular task. The CPU uses the instruction decoder and decodes the instructions into commands.

• Execute: The CPU activates all the computer parts required to perform the given task. The related task is then processed or executed.

• Write: The CPU sends the results back to memory. Depending on the size of the results, it is stored either in the CPU’s memory or in RAM.

There are mainly three types of CPU, such as:

• Transistor type CPU

• Small Scale Integration type CPU

• Large Scale Integration type CPU

In common terms, computers’ CPU is classified as: single-core, dual-core, quad-core, hexa-core, octa-core, and so on. Multi-core set-ups are similar to installing multiple, separate processors in a single computer. Because all the cores (multiple single processors) are mounted on the same board and plugged into the same socket, the connection between them is fast, making multitasking accordingly faster.

CPU (stands for Central Processing Unit) is the primary unit of the computer system and is responsible for executing/processing the instructions on the computer. Computers have some other processor or processing units, such as a graphics processing unit, but the term processor simply means CPU. The CPU is placed in a specific area on the mainboard (motherboard) of the computer, which is called the CPU socket.