Input and Output devices of a computer.pptx
- 1. Input and Output devices of a computer
- 2. Input Device is composed of a device that accepts data and instructions from the user or from another computer system Output Device is any piece of computer hardware that displays results after the computer has processed the input data that has been entered.
- 3. 1. Keyboard Entry – Data is inputted to the computer through a keyboard. Keyboard - The first input device developed for the PC. Data is transferred to the PC over a short cable with a circular 6-pin Mini-din connector that plugs into the back of the motherboard. Two (2) Types of Input Devices
- 4. 2. Direct Entry – A form of input that does not require data to be keyed by someone sitting at a keyboard. Direct-entry devices create machine-readable data on paper, or magnetic media, or feed it directly into the computer’s CPU.
- 5. 1. Pointing Devices - An input device used to move the pointer (cursor) on screen. Mouse - The most common 'pointing device' used in PCs. Every mouse has two buttons and most have one or two scroll wheels. Three Categories of Direct Entry Devices
- 6. Touch screen- A display screen that is sensitive to the touch of a finger or stylus. Used in myriad applications, including ATM machines, retail point-of-sale terminals, car navigation and industrial controls. The touch screen became wildly popular for smart phones and tablets.
- 7. Light Pen - A light-sensitive stylus wired to a video terminal used to draw pictures or select menu options. The user brings the pen to the desired point on screen and presses the pen button to make contact.
- 8. Digitizer Tablet - A graphics drawing tablet used for sketching new images or tracing old ones. Also called a "graphics tablet," the user contacts the surface of the device with a wired or wireless pen or puck. Often mistakenly called a mouse, the puck is officially the "tablet cursor."
- 9. 2. Scanning Devices- A device that can read text or illustrations printed on paper and translates the information into a form the computer can use. Bar Code Reader Image scanner
- 10. 3. Voice- Input Devices - Audio input devices also known as speech or voice recognition systems that allow a user to send audio signals to a computer for processing, recording, or carrying out commands. Audio input devices such as microphones allow users to speak to the computer in order to record a voice message or navigate software. Microphones
- 11. 1. Computer Display Monitor- It displays information in visual form, using text and graphics. The portion of the monitor that displays the information is called the screen or video display terminal. Output Devices
- 12. a. CRT Monitors - Cathode Ray Tubes (CRT) were the only type of displays for use with desktop PCs. They are relatively big (14" to 16" deep) and heavy (over 15 lbs). Types of Monitor
- 13. b. LCD Monitors – Liquid Crystal Display (LCD) technology has been used in laptops for some time. It has recently been made commercially available as monitors for desktop PCs. c. LED Monitors (Light Emitting Diode) - A display and lighting technology used in almost every electrical and electronic product on the market, from a tiny on/off light to digital readouts, flashlights, traffic lights and perimeter lighting.
- 14. 2. LCD Projectors- utilize two sheets of polarizing material with a liquid crystal solution between them. An electric current passed through the liquid causes the crystals to align so that light cannot pass through them. Each crystal, therefore, is like a shutter, either allowing light to pass through or blocking the light.
- 15. 3. Smart Board - A type of display screen that has a touch sensitive transparent panel covering the screen, which is similar to a touch screen.
- 16. 4. Printer - A device that prints text or illustrations on paper.
- 17. a) Ink-Jet or Bubble-Jet Printer - spays ink at a sheet of paper. Ink- jet printers produce high-quality text and graphics. b) Laser Printer - Uses the same technology as copy machines. Laser printers produce very high quality text and graphics. c) LCD and LED Printer- Similar to a laser printer, but uses liquid crystals or light-emitting diodes rather than a laser to produce an image on the drum. d) Line Printer - Contains a chain of characters or pins that print an entire line at one time. Line printers are very fast, but produce low-quality print. TYPES OF PRINTER
- 18. (e) Thermal Printer- An inexpensive printer that works by pushing heated pins against heat-sensitive paper. Thermal printers are widely used in calculators and fax machines. 5. Speakers - Used to play sound. They may be built into the system unit or connected with cables. Speakers allow you to listen to music and hear sound effects from your computer.