1. INPUT & OUTPUT Devices CHAPTER II INPUT & OUTPUT Devices “The devices used in computer system to enter data into a computer or extract data from a computer are known as I/O devices “ INPUT & OUTPUT Devices Input/output devices are used for communication with the computers. Thousands of kinds of I/O devices are available today and the number is growing rapidly. A few of the more common ones are listed below:

4. Keyboards as Input Devices QWERTY keyboard Dvorak keyboard alphabetical keyboard chord keyboard numeric keypad [ Mustillo ] A keyboard designed for speed typing. keyset or chorded keyboard (chord keyboard or chording keyboard) is a computer input device that allows the user to enter characters or commands formed by pressing several keys together, like playing a "chord" on a piano.

5. Ergonomical Dvorak Keyboard http://www.ergocanada.com/images/dvorty_2001dqe.jpg virtual keyboard A virtual keyboard is also called a projection keyboard.

6. Input Devices Keyboard Ergonomic keyboards Compact Keyboard Multimedia and Gaming Keyboards Virtual Keyboards Point and Draw Devices Mouse Mechanical Optical Joystick Trackball Digital Pad Mouse Pen Track Pads Image Scanner Digital Camera Mouse Pen Hold it like a pen, draw, sketch, create and mouse on a pad, fits in your pocket, is wireless and works for PC's and Macs.

7. An optical computer mouse uses a light- emitting diode to detect movement relative to a surface, unlike a mechanical mouse which has a ball which rotates

12. Digital Pad Take Notes Connect to the Pc Organize Your Notes 4. Send via e-Mail

13. Principles of Information Systems, Eighth Edition 13 Input Devices Personal computer input devices Keyboard Mouse Speech-recognition technology Input devices that recognize human speech e.g. automate account identification process Digital cameras

14. Principles of Information Systems, Eighth Edition 14 Input Devices (continued) Scanning devices Optical data readers Special scanner OMR – Optical mark recognition (also called optical mark reading and OMR) is the process of capturing human-marked data from document forms such as surveys and tests. OCR – convert handwritten to typed doc into digital data Magnetic stripe card Swipe card Point-of-sale (POS) devices Used in retail operations to enter sales information

15. Principles of Information Systems, Eighth Edition 15 Output Devices Display monitors Liquid crystal displays (LCDs) Printers and plotters Digital audio player

16. PRINTERS A device that prints text or graphics on paper. Printers are connect with computers through “Printer Cable” or “Printer USB Cable”. In a network mode, printers have a LAN Port. There are many different types of printers. In terms of the technology utilized, printers fall into the following categories:

17. Dot matrix Printers A type of impact printer that produces characters and graphics by striking pins against an ink ribbon to print closely spaced dots in the appropriate shape. Dot-matrix printers are relatively expensive and do not produce high-quality output. However, they can print to multi-page forms (that is, carbon copies), something laser and ink-jet printers cannot do. But Dot matrix printers make a lot of noise. Ink: Dot Matrix Printer use ribbon for ink

18. Ink-jet Printers A type of printer that works by spraying ionized ink at a sheet of paper. A typical ink-jet printer provides a resolution of 600 dots per inch, although some newer models offer higher resolutions. In general, the price of ink-jet printers is lower than that of laser printers. However, they are also considerably slower. Another drawback of ink-jet printers is that they require a special type of ink. Ink: Ink-Jet Printers use Ink Cartridges

19. Laser Printers A type of printer that utilizes a laser beam to produce an image on a drum. The light of the laser alters the electrical charge on the drum wherever it hits. The drum is then rolled through a tank of toner, which is picked up by the charged portions of the drum. Finally, the toner is transferred to the paper through a combination of heat and pressure. This is also the way copy machines work. Ink: Laser Printers use Toner Cartridges

20. Multiple function printers Printer, copier, Fax Machine and Scanner

21. PLOTTERS The plotter is a computer printer for printing graphics. Plotters are different from printers. Plotters draw lines using pen. As result they can produce continuous lines. Plotters are expensive than printers. Pen plotters print by moving a PEN or other instrument across the surface of a piece of paper. Plotters offered the fastest way to efficiently produce very large drawings or color high-resolution ARTWROK.

22. Principles of Information Systems, Eighth Edition 22 Computer-based navigation systems GPSs (Global positioning system), satellite based radio navigating system Guide to specific destination

23. Liquid-crystal display Light-emitting diode organic light-emitting diode Plasma display

24. CRT -MONITORS Some computer monitors generate output with the help of cathode ray tubes. This type of device is called the CRT (or, cathode ray tube) monitor. However, CRT monitors can be bulky and take up a lot of desk real estate, be very heavy to carry, and they require a lot of power to run properly. Moreover, the picture screen can distort, display a "flicker effect," or burn out over time.

25. LCD and Plasma Monitors The newer types of display units are liquid crystal display monitors (or, the LCD monitor) and plasma screen monitors. LCD and plasma screen styles are much lighter than their older CRT counterparts. LCD models in particular require less power to run. However, these newer models can be more expensive than traditional computer monitors. LCD (Liquid Crystal Display) computer monitors save a lot of space and can even be mounted on walls. They provide a wide viewing angle and come in sizes typically ranging from 17-inches to 60-inches.

26. OLED-Monitors OLED (Organic Light Emitting Display) computer monitors are much thinner and brighter than LCD or Plasma screens. OLED monitors can also be placed on transparent surfaces, such as glass, allowing the user to see through them when not active.

27. Touchscreen - Monitors Touchscreen computer monitors provide a new way of interacting with your computer with a touch-sensitive screen. This allows users to interact directly with the application on screen without need for a mouse or keyboard. Touch computers play a prominent role in the design of digital appliances such as the personal digital assistant (PDA), satellite navigation devices, mobile phones, and video games.

28. Other Output Devices Secondary Storage Devices Hard Disk CD/DVD Pen Drive Camera Fax Machine Speakers Headphone Projector