What is a computer?

Computer is a modern very fast electronic device. Other electronic devices cannot do more than two or three tasks. But with the help of computer, many difficult tasks can be done perfectly. Two main features of computer are 1. It can store millions of data 2. Able to follow instructions with great speed and accuracy.

The word computer comes from the Greek word compute. The word compute means to calculate. Basically the word computer means calculating machine. (again from the Latin word Computare and the origin of the word Computer) Earlier, only accounting work was done with computers. Computer language is based on electronic signals. The computer expresses the result based on the instructions given to the computer through the computer language. This language of the computer is the computer program. A computer without programs is an inanimate object.

Introduction to Computer:

A computer is a device that receives data and processes it according to instructions. The result after processing can be used in the form of information in the form of data or signals automatically to operate another machine or to use in any other process. Currently, all the operations of the computer that we see are conducted by processing data through numbers (Digit) with the help of electron (ie electricity) flow. For this they are called electronic digital computers.

The microcomputer or personal computer (PC) is the smallest type of computer widely used today. A complete personal computer system consists of a microprocessor and peripheral components, primary storage, one or more circuit boards with input/output circuits, input/output and secondary storage devices. All these devices or parts and everything that can be held or touched by the computer are called computer hardware. And all the programs (which are a series of instructions) used to operate the computer or make it usable are called software. Below is a brief description of the main hardware of a personal computer.

Input device:

To process data or programs in a microcomputer, human-understandable characters, numbers or instructions are first passed to the computer memory through an input device known as input. The computer converts this information or instructions into binary code in its understandable language. In binary system, numbers are expressed with only two numbers or digits 0, 1. One of these two digits is called a bit. Bit is short for Binary Digit. A unit of eight bits is called a byte. An English mathematician named George Bulley discovered this binary system in 1854. After converting to binary code it is sent to primary memory through digital electrical signal. From there they are used in different parts of the computer as needed. Direct communication between the computer and the driver is established through the input device. Input devices include keyboard, mouse, The physical optical scanner, and the lightpen are notable. Floppy disks and hard disks also often serve as input devices in computers.

Keyboard: Keyboard is the most widely used input device in computers. Looks like the first half of a typewriter and the keys are arranged almost the same. The keys on this keyboard act as special electronic switches. Each key press produces a series of digital electrical pulses specific to a particular character or statement and sends them to primary storage. A character is any letter, number, punctuation or special symbol like – #, &, > etc. Any instruction written in a program is called a statement. Modern keyboards typically have the following keys in addition to the alphabetic keys and the spacebar.

Numeric Keys: Pressing these keys produces digital electrical impulses from 0 to 9. In many cases they are located to the right of the main keyboard, as a key pad. And they are easily used for any long mathematical calculations or data entry work.

Cursor control key: The small light symbol on the monitor where the computer will display a new character i.e. the place where the new entry will take place is called the cursor. Cursor control keys can be pressed to move the cursor in any desired direction.

Function Keys: All keys that can be pressed to give special statements/instructions are called function keys.i
Backspace key: The key that can be used to delete the text to the left of the cursor and move the cursor to the left is called the backspace key.

Enter or Return Key: This key is used to go to the next paragraph or command to execute an instruction. Sometimes multiple keys can be pressed simultaneously or in sequence to perform specific actions.

Mouse: If this small electronic device is connected to the computer, it can be placed on the table or any flat place and the cursor can be moved in different directions as desired or any command can be given to the computer by choosing a task described on the screen.

Optical Scanner: It uses any printed part or image to be converted into digital signal and sent to the primary storage and stored in the secondary storage which can be modified/enhanced later as desired.

Light pen: By using it, the visible part of the computer monitor can be easily changed in a short time with the help of touch.

Central Processing Unit (CPU) The CPU is the main part of the computer. It consists of a circuit board containing the main microprocessor, additional microprocessors (such as microprocessors that control the functions of input-output devices), other active components and chips, interconnected by means of a bus or highway. The means of exchanging electrical signals from one part to another in a computer is called bus or highway. It is a bundle of wires or very fine conductive lines on a computer chip. Data processing, instruction execution and all other functions of the computer are controlled through this CPU. CPU consists of three main parts. Namely –

1. Arithmetic Logic Unit (ALU)
2. Storage (Storage)
3. Control

Classification of Computers:

A computer converts a set of electrical waves into its own signals and solves problems with the help of commands applied by the user. Computers can be divided into two categories based on the difference in application. Namely–
1. General practical computer.
2. Special practical computer.

It can be divided into three parts based on the principles of computer structure and circulation.
1. Analog Computer.
2. Digital computer.
3. Hybrid computer.

Digital computers can again be divided into four categories based on size, capabilities, price and importance of use.
1. Micro computer.
2. Mini computer.
3. Mainframe computer.
4. Super computer.

Microcomputer is again divided into three parts:
1. Laptop computer
2. Desktop computer
3. Super Micro Computer

Below is the complete classification of computers:

Analog Computer: A computer that can measure one quantity relative to another quantity is an analog computer. It can record temperature or other measurements that change regularly. A motor vehicle speedometer is a classic example of an analog computer.

Digital Computer: Digital computer is expressed by two types of electrical voltage. Presence of voltage is represented by 1 and absence by 0. It can perform any arithmetic addition and other operations like subtraction, multiplication and division. All modern computers are digital computers.

Hybrid Computer: A hybrid computer is a computer that combines the best features of analog and digital computers. It is used in scientific research. So it can be said that hybrid computer is a partial combination of analog and digital computer in terms of technology and foundation. Generally, hybrid computers collect data in analog mode and perform calculations in digital mode. For example, the hybrid computer used in the meteorological department calculates the weather by measuring the air pressure, temperature etc. in the analog method and calculates it in the digital method.

Mini Computer: A computer terminal that can be used by more than half a hundred users at the same time is a mini computer. It is used in industry, commerce and laboratories. Eg – pdp-11,ibms/36,ncrs/9290, IBM 9375. pdp-11,ibms/ 36,ncrs/9290, IBM 9375.

Microcomputer: Microcomputer is also called personal computer or PC. Interface chip (Mother Board), a microprocessor cpu, ram, rom, hard disk etc. Simultaneously the microcomputer was formed. everyday The use of this computer can be seen in all areas of life. Macintosh IBM PC is such a computer.

Super Computer: A very powerful and fast computer is called a super computer. The speed of this computer is about 1 billion characters per second. A supercomputer is a computer with large memory to handle large data such as the census of a country. Computers like CRAY 1, supers xll.

Tablet Computer : Tablet computer is a type of micro computer. Which is known as palm top computer. It is a touch screen technology. It runs on Android and Windows operating systems.
So today I just learned computer basics.

click here to view next post .

Thanks everyone