​All general-purpose computer systems require the following hardware components:

• ​Memory: Memory enables a computer to store, at least temporarily, data and programs.

• Mass storage device: This allows a computer to permanently retain large amounts of data. Common mass storage devices include solid state drives (SSDs) or disk drives and tape drives.

• Input device: Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer.

• Output device: An output device is a display screen, printer, or other device that lets you see what the computer has accomplished.

• Central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions.

• A motherboard: This component allows all of the other components to communicate with one another.

WHAT ARE THE DIFFERENT TYPES OF COMPUTERS?

On the basis of size, there are four types of computers:

1. ​​Supercomputer

2. Mainframe computer

3. ​Minicomputer

4. ​PC (Personal Computer)

​Supercomputer

They are the biggest and fastest computers (in terms of speed of processing data). Supercomputers are designed such that they can process a huge amount of data, like processing trillions of instructions or data just in a second. This is because of the thousands of interconnected processors in supercomputers. It is basically used in scientific and engineering applications such as weather forecasting, scientific simulations, and nuclear energy research. It was first developed by Roger Cray in 1976.

​Characteristics of Supercomputers:

• Supercomputers are the computers which are the fastest and they are also very expensive.

• It can calculate up to ten trillion individual calculations per second, this is also the reason which makes it even more faster.

• It is used in the stock market or big organizations for managing the online currency world such as bitcoin etc.

• It is used in scientific research areas for analyzing data obtained from exploring the solar system, satellites, etc.

​Mainframe computer

Mainframe computers are designed in such a way that it can support hundreds or thousands of users at the same time. It also supports multiple programs simultaneously. So, they can execute different processes simultaneously. All these features make the mainframe computer ideal for big organizations like banking, telecom sectors, etc., which process a high volume of data in general.

​Characteristics of mainframe computers:

• It is also an expensive or costly computer.

• It has high storage capacity and great performance.

• It can process a huge amount of data (like data involved in the banking sector) very quickly.

• It runs smoothly for a long time and has a long life.

​Minicomputer

Minicomputer is a medium size multiprocessing computer. In this type of computer, there are two or more processors, and it supports 4 to 200 users at one time. Minicomputers are used in places like institutes or departments for different work like billing, accounting, inventory management etc. It is smaller than a mainframe computer but larger in comparison to the microcomputer.

​Characteristics of minicomputers:

• Its weight is low.

• Because of its low weight, it is easy to carry anywhere.

• less expensive than a mainframe computer.

• It is fast.

​Personal Computer

It is also known as a microcomputer. It is basically a general-purpose computer and designed for individual use. It consists of a microprocessor as a central processing unit (CPU), memory,  input unit, and output unit. This kind of computer is suitable for personal work such as making an assignment, watching a movie, or at office for office work, etc. For example, Laptops and desktop computers.

​Characteristics of microcomputers:

• In this limited number of software can be used.

• It is smallest in size.

• It is designed for personal use.

• It is easy to use.