What a computer performs

What a computer performs

A computer is a machine that can be instructed to carry out sequences of arithmetic or logical operations automatically via computer programming. Modern computers have the ability to follow generalized sets of operations, called programs. These programs enable computers to perform an extremely wide range of tasks. A "complete" computer including the hardware, the operating system (main software), and peripheral equipment required and used for "full" operation can be referred to as a computer system. This term may as well be used for a group of computers that are connected and work together, in particular a computer network or computer cluster.

Computer system

Computer system definition

A computer system is an electronic system consists of many parts works together to make the computer work. Computers work mainly to perform a specific task given by the user.

In a desktop computer, we see three parts of the computer such as input unit (keyboard and mouse), output unit (monitor and printer), and system unit (rectangular box).

Important components of computer system

Generally, a computer system consists of four important components:

• 
  Input unit
  
• 
  CPU (Central Processing Unit) 
  
• 
  Output unit
  
• 
  Memory unit
  

Input unit

An input unit consists of input devices such as keyboard, mouse, scanner, and joystick. Input devices are used to send data to the computer.

An input device accepts the instructions and data from the user and converts it into the form, which is understandable to the computer. The converted data is send to the CPU (Central Processing Unit) for further processing. The various input devices include:

• 
  Keyboard
  
• 
  Computer mouse 
  
• 
  Scanner
  

Keyboard

The name itself suggests that it is a board consists of arrangement of keys. It is the main input device for most of the computers.

Keyboard is an input device used mainly for entering symbols like letters and numbers into a computer. Input is entered into the computer by pressing buttons or keys. Generally, it is used for typing text and numbers on ms word, note pad, and other programs. Keyboards are also used for playing games.



Computer mouse

A computer mouse is an input device used for selecting items, opening, and closing items, copying and deleting the items on the screen by controlling the movement of a cursor or pointer on the computer screen. It is also used for creating new folders and browsing internet.

The mouse turns the movement of the hand (left, right, forward, and backward) into equivalent electronic signals that in turn are used to move the pointer.

Scanner

Scanner is an input device used mainly for capturing the printed documents and uploading it into computer as digital images. These digital images are easily viewed and edited on computer. A scanner can be connected to a computer via USB or SCSI.

Output unit

An output unit consists of output devices such as monitor, printer, and speaker. The output devices display the result (which is obtained after processing the data) to the user in an understandable manner.

The various output devices include:

• 
  Monitor
  
• 
  Printer
  
• 
  Speaker
  

Monitor

Monitor is the electronic visual display for computers. It is the most important output device of a computer. Without monitor we cannot see what computer is doing or performing inside.

Printer

Printer is an output device used to print text, images, photos, or anything on a paper. The various types of printers include laser printer, 3D printer, Ink-jet printer, plotter, dot matrix printer, thermal printer, daisy wheel printer, line printer, etc. The printers print the text or objects on a paper either in black and white or colored form.

Speaker

The speaker is an output device that converts the electronic signals from the computer into audio signals. The user easily hears these audio signals and understands it. Sometimes headphones are also used for listening songs and music from a computer. The speakers are generally connected to a computer via cables. In some computers like laptops, the speakers are built-in.

Zubaydo Ikandarova

Direction of Informatics teaching

methodology Level 3 2^nd group student