Fundamentals of a Computer

Computer Hardwares

Defination :
• The Physical components of a computer are known as Hardwares of a computer.
  or The devices of a computer that can be seen or touched physically are known as hardwares of a computer.
• All input, processing and output devices are comes under hardware.
• Some hardware devices are Keyboard, Mouse, Joystick, Light Pen, Trackball, Graphic Tablet, Scanner, Microphone, Magnetic Ink Character Reader(MICR), Optical Character Reader(OCR), Bar Code Reader, Optical Mark Reader(OMR), Webcam, CPU, Monitors, Printer, Plotter, speaker etc.

Some hardwares are explained below :-
• Keyboard : A Keyboard is an input device, used to enter data into the computer. It is used to type letters, numbers and symbols.
• Mouse : A Mouse is an input device, used to point/select an item. It has three buttons i.e. Left, Right and scroll button.
• Joystick : A joystick is most widely used input device used for playing games on a computer. It has a rod and a ball attached to its lower end.
• Light Pen : A light pen is a light-sensitive wand that is connected to a Visual Display Unit. It is an input device, used to point to objects onscreen and draw on the screen.
• Trackball : A Trackball is an upturned mouse in which the ball is present on top or on side. Instead of moving the whole device, you need to just move the ball with fingures.
• Scanner : A Scanner is an input device, used to scan or copy written documents and photographs into a computer. It convert the file into digitised format.
• Microphone : A Microphone is an input device, used to input sound into a computer. It detects the sound and transmit electric signals to a computer.
• MICR : It stand for Magnetic Ink Character Recognition. It is an input device, used to read the magnetic code written on cheques or on credit cards.
• OCR : It stand for Optical Character Recognition. It is an input device that allows direct reading of any printed character written in a specific font. The printed matter is scanned with a photoelectric device.
• OMR : It stand for Optical Mark Reader. It is an input device, used to reads the marks made by pencils or a pen on a printed form. Example - evaluation of MCQ papers.
• BCR : It stand for Bar Code Reader. It is an input device, used to read the pattern of bars on items you buy from the market.
• Webcam : A webcam is a camera usually placed on the top of a computer monitor. It is an input device, used to take pictures and record videos.
• Printer : A Printer is an output device, used to print the output generated by the CPU on a paper. It can be classified into two types :-
  1. Impact Printers : An Impact printer is a printer in which the paper comes in direct contact with the printer head during printing.
     Examples are Daisywheel Printer, Dot Matrix Printer etc.
  2. Non-Impact Printers : A Non-Impact printer is a printer in which the paper does not comes in direct contact with the printer head during printing.
     Examples are Laser Printer, Inkjet Printer etc.
• Plotter : A Plotter is an output device, used to print graphics, diagrams and maps.