HARDWARE

The components or devices that are connected to a computer are collectively known as hardware.For example monitor,mouse,Keyboard,speakers,     and printer come under the term Hardware.

Input-Output devices: As you know, a computer follows the I-P-O cycle for processing.Therefore all the devices can be categorized as input devices,output devices,and processing devices.The input devices are used to give instructions to the computer.For example Mouse and keyboard are  input devices.The output devices are used to display output of an operation.For example Monitor and printer.

Keyboard:The Keyboard has already been identified as input device.This is a component that closely resembles a typewriter console.The keyboard provides different keys to perform various operations.

Mouse: A mouse is a small device that is connected to the system by means of a long wire.This is another input device,whose movements causes corresponding movement of a pointer on the screen.It usually has two or three buttons using which the user can select options from the screen.

VDU: Now that you are familiar with some of the input devices of the computer,let us take a closer look at an output device.VDU is the abbreviated form of Visual Display Unit.Data that has been processed needs to be displayed to the user.This is done using the monitor or the VDU.The VDU is similar to that of a TV screen and can display both text and graphic images.The display can be either in Black and white or in color.

Printer: The output on the VDU cannot be stored for later reference.For a permanent,you would require a printer that is also an common output device.Using the printer,you can obtain the output on paper.Printers are capable of printing at a very high speeds.The printers commonly used with the PC are the dot matrix printer,the ink-jet printer and the laser printer.

Microphone: A microphone is an input device that allows a user to speak to the computer to enter data and instructions into the computer or it is used to record sound.

Joystick: A joystick is a pointing device with a vertical lever mounted on a base.It is mainly used for computer games and ultra sound scanners in hospitals.

Scanners: A scanner is an input device used to capture information,such as photographs and documents on paper and translate the information into a raster computer image.

Speakers: You can use speakers on a multimedia machine to listen to the sound files,which can be audio,recorded by audio Cd's or Microphone.