Short Essay on the Concept of Hardware


Computer contains a number of components for processing the information. The major components are – Hardware & Software.


Hardware represents the physical and tangible components of the computer itself i.e. components which can be seen and touched. It includes

  • Input devices.
  • Output devices.
  • Central Processing Unit.
  • Memory.


All input and output devices connected to computers are collectively known as peripherals.

Input Units:

Input units provide communication between man and machine. Input of any form from input device is converted into binary signals so that it can be understood by CPU. This process is known as digitizing. Input data may be text, graphics, audio, video or combinations.

Some Common Computer Input Devices:



Used to type data into the computer Most common input device today

Has special keys for giving the computer commands. Commands tell the computer to do something, like save the file. These special keys are called command or function keys.

Pointing Devices


Pointing devices move some object on the screen and can do some action. Common pointing devices are mouse, track ball, game consoles etc.


A scanner allows you to scan documents, pictures, or graphics and view them on the computer. You can also use software to edit the items you scan.

  • Used to put printed pictures and text into a computer.
  • Converts an image into dots that the computer can understand.
  • To scan text, optical character recognition (OCR) software is needed.

Digital Camera

  • Used to take electronic pictures of an object.
  • The pictures taken by a digital camera can be used directly by a computer.



  • Used to put sound into a computer.
  • Need sound recording software Scanner.


  • Can be used to put both sound and images into a computer.
  • Use a laser to read a Compact Disk (CD) or a DVD disk.

Video Capture Card

  • Usually place inside the computer’s case.
  • Use to put video into a computer.
  • Need a video source, either a video camera or video recorder.


Central Processing Unit (CPU):

CPU is the brain and heart of a computer. It runs user input instructions, processes them and finally provides the output.

Today, all CPUs are microprocessors

  • A microprocessor is a complete computer on a silicon chip.
  • A microprocessor does all of the functions of a computer.
  • Stores data and instructions waiting to be used.
  • Follows changeable instructions.
  • Does input, processing, and output.

CPU has three major component Arithmetic and Logical Unit (ALU), Control Unit (CU) and Memory Unit (Registers).

The Arithmetic and Logic Unit (ALU) carries out all mathematical and logical operations in a computer.

The Control Unit directs the flow of information into the CPU and /or memory or storage. It controls which instructions the CPU will do next.

Memory units in a CPU are known as Registers. These are small memory locations of definite size which stores data and instructions on temporary basis for processing.

The size of the registers are given by the word length which in turn is expressed by no of bits making a word. The size of the register directly determines the speed and performance of a processor. Speed of a CPU

  • The speed of a CPUs is measured in hertz (Hz).
  • A hertz is one cycle per second.
  • All computers possess built in clocks for timing the cycles.
  • The clock is usually located in a small metal box on the motherboard.
  • Today, many CPUs can complete over six (6) instructions per second.
  • Contemporary microprocessors can operate with speed of around 2 gigahertz.
  • 1 giga hertz (GHz) = 109Hz

Output Units:

Output devices are used to provide output to environment. The output coming from the CPU is in theorem of electronic binary signals which needs conversion in the form which can be understood by human being.

The output can be provided to monitor screen or visual display units, printers, plotters, loaders and speech synthesizers etc.

Some Common Output Devices:

Monitors and Displays

  • Shows the processed information on a screen.
  • A monitor or display produce a soft copy. When the device is turned off the information goes away.
  • Monitors are slowly being replaced by flat panel displays.


  • Printers produce a hard copy.
  • The information is printed on paper and can be used when the device is off.
  • It is also called a printout.


  • used to output sound


Memory is used for storing information’s. It is mainly classified into two type’s internal memory and External memory. The internal memory is further classified into CPU and Main memory. CPU memory is registers and on chip cache. Main memory is classified as Random Access Memory (RAM) and Read Only Memory (ROM).

External memory is the attached or extended memory. Magnetic disk, Magnetic tape and optical disk are coming under these categories.

Some Common Storage Devices

Hard Drive

The hard drive is the primary device that a computer uses to store information. The hard drive stores programs, data files, saves files, and organizes files. The hard drive is located inside the computer case. The hard drive, magnetically stores data on stacks of rotating disks called platters.

Floppy Drive

The floppy drive stores and retrieves information on a floppy disk.

CD -ROM Drive

CD-ROM is a device that reads information stored on a compact disc. CD- ROM stands for Compact Disc Read Only Memory. One CD is equal to the space in over 40 floppy disc.

Removable Hard Disk

A zip disk is a removable disk that holds a large amount of information. A zip disk can be used to achieve, protect and transfer large amounts of data.

Web Analytics Made Easy -
Kata Mutiara Kata Kata Mutiara Kata Kata Lucu Kata Mutiara Makanan Sehat Resep Masakan Kata Motivasi obat perangsang wanita