Input Unit :
An input is everything that we tell the computer. Input unit is comprised of the input devices attached to the computer system. These as the name suggest are used to feed data and instructions to the computer, on the basis of which the processing starts. Examples of input units are Keyboard, Mouse, Magnetic Ink Character Reader (MICR), Optical Mark Reader (OMR) etc.User's Response : The user's answer to the computer's questions
Task of Input Units
- It accepts data and instructions from the user.
- It converts the accepted instructions into the machine language.
- It gives cony env& instructions to CPU for processing.
Various Input Device
Track BallIt is used as an alternate of mouse. The user has to move its ball in order to utilise it that causes the pointer to move on the screen.
Joystick
It is very popular among the people fond of computer games, but today different types of game controllers are replacing them gradually. Joystick is used to control the machine such as crane in the process of building constructions.
Digital Camera
Digital camera can take the images and also records the videos. The images and videos taken by digital cameras are recorded in files. These files can get copied into the computer that can be further edited for many purposes.
Microphone
Microphone is used to input the sound. It can be used to enter text in any word processing application with voice recognition software in the computer.
Touch Screen
There is a network of light rays in touch sensitive visual display unit or in screen that recognises the touch. Touch screen is used in many mobile phones. They are often used in cash machines and shopping centres.
Video Digital
Video digital takes the images from video camera or television and stores it into the computer for further use. The video sequences taken by video digital are mainly used in multimedia presentation.
Scanner
Scanner is used to convert an image into its digital form. It is similar to photocopier but it makes digital copy of an image instead of its hard copy. It
is used to scan the text with the software optical character recognition.
Graphic Tablet
There is a flat pad on the graphic tablet upon which an user writes with the help of a special pen. Pictures can also be drawn on the screen using that
pen in this way.
Magnetic Ink Character Recognition (MICR)
Magnetic Character Recognition machineare capable of reading magnetic ink character on MICR documents. This technology is used to automatically read those frustrating-looking numbers on the bottom of the cheque. A special purpose machine known as a reader/sorter reads characters made of ink containing magnetised particles. A related technology is the magnetic strip, used on the back of credit cards and bank debit cards, that allows readers, such as Automatic Teller Machines (ATMs) to read account information and facilitate monetary transactions.
Optical Character Recognition (OCR)
Optical Character Recognition devices can read data that has been typed or handwritten on a source document. It is a combination of a scanner and a special software, which converts the pnnted or handwritten data to ASCII. It is used to convert paper record into electric filling and scanned chalan into a spreadsheet.
Web Camera
A web camera is used to view images on the Internet. Using it with the help of Internet we can view the photo of a far away person, but he should also have a web camera.
Optical Mark Recognition(OMR)
Optical Mark Recognition (OMR) also called Mark Sensing, is a technology where an OMR device senses the presence or absence of a mark, such as a pencil mark. OMR is used in tests, such as aptitude tests for different competition/entrance examinations.
Output Unit
An output is data that has been processed into useful form, now called information. Output unit is comprised of the output devices attached to the computer system. Examples of output devices are Printers, Plotters, Visual Display Unit (Monitors), Floppy Disk Drive, Speakers, Pen Drive etc.Tasks of output unit
- It accepts processed data from CPU.
- It converts results from machine language into simple language.
- It displays results to user.
- It prints results on paper or other permanent media.
Hard Copy : This output is printed on paper or other permanent media.
Soft Copy : This output is displayed on screen or by other non-permanent media.
Some commonly used output devices are
- Monitor
- Plotter
- Printer
- Computer Output Microfilm (COM)
- Speaker
- Sound Card
- Screen Image Projector
- Head Phones
- The means through which computer gives output are known as Output Devices.
Various OutPut Devices :-
Video display screen fixed in hard layer and computer is also known as Monitor or Video Display Terminal. Monitor means only that devices in which there is noany electronic device other than the device required for showing the image.
various Names of Monitor
- Screen : Computer Screen or Display Screen
- VDT : Video Display Terminal
- CRT : Cathode Ray Tube
- VDU : Visual Display Unit
Projector is that hardware device which projects an image on the flat surface like on computer screen. These devices are generally used in meetings, seminars and presentations because each person can easily see the image projected by it sitting in a big room.
Printer
Printer is that external hardware device which gives the output in printed format after receiving data from computer. This is such an operated external device used with computer that prints text, image or photo.
Impact Printers :-
- Doi Matrix
- Daisy Wheel
- Chain and Bland
- Ink let
- Thermal ( Page
- laser
It is also known as Sound Board or Audio Card. Sound card is an expansion card or unified circuit that enables computer to produce sound through speaker or headphone.
Speaker
It is the device which presents the sound produced during any programme. This is connected to sound card and gives the sound produced by card in the form of output.
Video Card
It is also known as Graphics Card, Video Board or Video Controller. This is an internal circuit board that allows the image displaying devices like monitor to display the images.