Computer and Its Components

What is Computer?

A Computer is an electronic machine which stores, reads and processes data to produce meaningful information as an output.

Computer and its components

Components of Computer:-

Input Device: 

Devices that are used to give instructions are called input devices. Input devices are Keyboard, Mouse, Joystick, Optical character reader, CDs, Bar code reader, Light pen, scanner, touch screen, MICR (Magnetic Link Character Recognition) etc.

Output Device:  

These are the devices that are used to display the results of processing of information or data.  Output devices are Visual Display unit, monitor, printer, speaker, pen drive, etc.

Central Processing Unit or CPU:  

CPU is the device that is used for the manipulation of information inside the computer. Central Processing Unit is too called as the brain of the computer. But it is commonly called as a processor.

Arithmetic Logic Unit or ALU:  

ALU performs all the logical and arithmetical functions and operations of the computer.

Control Unit or CU:  

Control Unit instructs, maintains, and controls the flow of the information or data.

What is Memory?

Memory holds the all raw and processed data, set of instructions and information inside the CPU.

Primary Memory:

Primary Memory stores the data which is in use currently by the computer. Primary memory is divided into two memories. One is RAM and other is ROM.

a)     1. RAM (Random Access Memory): It is a volatile memory. It is a temporary storage.

·  DRAM - Dynamic Random Access Memory.

·  SRAM -  Static Random Access Memory.

b)     2. ROM (Read Only Memory):  It is a non-volatile memory where all logical data is stored that cannot be changed.

·   PROM – Programmable Read Only Memory.

·   EPROM – Erasable Programmable Read Only Memory.

·   EEPROM –  Electrically Erasable Programmable ROM.

   Secondary Memory:

  It stores data, program, information, and instruction permanently.

Cache Memory:

Cache Memory is a temporary storage. In Cache memory, the data are frequently accessed can be stored for rapid access.

What is Hardware?

Hardware is any peripheral device which can be seen and touched. Computer hardware includes input devices, storage devices, output devices and processing devices.

What is Software?

Software is a set of instructions that leads the computer to process the information. It can be classified into –

a)    a) System Software: It is background software that helps the computer to manage its own internal resources like operating system, device driver, language translator etc.

b)    b) Application Software: It is a set of programs designed for specific uses or purposes or applications like word, processor, spreadsheets, accounting programs etc.

Networking:

Computer networking relates to the communication between a group of two or more computers linked together. The common example of networking is the Internet. Internet connects millions of people all over the world together. According to size and scale, computer network can be categorized into three areas –

a)   a) Local Area Network (LAN):  It is a graphical area spread over 1 km to 10 km or within a same building.

b)   b) Metropolitan Area Network (MAN):  It is a graphical area spread over o city or town.

c)   c) Wide Area Network (WAN):  It is a graphical area spread over countries.

What is Operating System?

It is a System Software, consisting of an integrated set of programs that control computer resources and provides common services for efficient execution of Various Application Software.

What is Internet?

It is the worldwide network and it is a publically accessible system of interconnected computer networks that transmit data by using the internet protocol.