Chapter 2 Peripheral Devices 1

2 What’s inside and on the CD? This chapter provides an overview on: –Keyboard and mouse –Specialized input devices Trackpads Digital cameras Joysticks –Display devices and printers –Voice synthesizers and plotters –Technologies that provide easiest connections –Component purchasing –Tips to help when shopping for a computer, software, and peripheral devices Practical Computer Literacy, 2 nd edition Chapter 2

3 What is a peripheral device? A peripheral device is any input or output component that connects to a computer Standard components include: –Keyboard –Mouse –Display unit –Printer Practical Computer Literacy, 2 nd edition Chapter 2

4 What is a peripheral device? Specialized peripheral devices include: –Playing games –Monitoring home security –Capturing video images Specialized peripheral devices are key components of large-scale computers –High-speed printers for mass mailings –High-speed optical character readers in banks –Computer-controlled robots for: Arc welding Circuit board assembly Painting Practical Computer Literacy, 2 nd edition Chapter 2

5 What is a peripheral device? –Handheld scanning devices keep track of package deliveries –UPC scanners in check-out lanes Practical Computer Literacy, 2 nd edition Chapter 2

6 What are the options for standard input devices? The keyboard is the most important input device on desktop and notebook computers –Design of keyboard is based on typewriter’s QWERTY layout –Additional keypad for editing –Function keys for computer-specific tasks –Numeric keypad Practical Computer Literacy, 2 nd edition Chapter 2

7 What are the options for standard input devices? Practical Computer Literacy, 2 nd edition Chapter 2

8 What are the options for standard input devices? Pointing devices manipulate on-screen pointer –Mice –Trackballs –Pointing sticks –Trackpads –Joysticks Practical Computer Literacy, 2 nd edition Chapter 2

9 What are the options for standard input devices? Practical Computer Literacy, 2 nd edition Chapter 2

10 What are the options for specialized PC input devices? A joystick looks like car’s stick shift –Controls objects on screen –Can be adapted for physical challenges that make it difficult to use keyboard A digital camera used to capture still images –Easily transferred to computer –Produce images that can be stored, manipulated, posted on the Web, and transmitted as attachments Practical Computer Literacy, 2 nd edition Chapter 2

11 What are the options for specialized PC input devices? A digital video camera captures moving images –Easily transferred to computer –Easily edited on computer A graphics tablet features pressure-sensitive surface and pen for free-hand drawing A digitizing tablet provides flat surface for vector drawing such as blueprints and technical drawings Practical Computer Literacy, 2 nd edition Chapter 2

12 What are the options for specialized PC input devices? A touch-sensitive screen can detect the location of a fingertip or stylus within the screen area A scanner converts images into bitmap graphics that can be viewed and edited with graphic software –Can capture old photographs –Scanned Text can be manipulated if scanner has optical character recognition Practical Computer Literacy, 2 nd edition Chapter 2

13 What are the options for specialized PC input devices? Standard microphone is used to collect audio input and is part of sound card –Some software has speech recognition to allow for voice commands instead of keyboard and mouse –Handy for narrations on Web sites and videos –Require lots of storage space Practical Computer Literacy, 2 nd edition Chapter 2

14 What are the most popular display technologies? LCD display produces image by manipulating light within layer of liquid crystal cells CRT display device, such as glass tube on standard TV Plasma screen creates image by illuminating miniature colored fluorescent lights in panel-like screen Practical Computer Literacy, 2 nd edition Chapter 2

15 What are the most popular display technologies? Performance of display device is factor of: –Screen size –Dot pitch –Response time –Color depth –Contrast ratio –Screen resolution Practical Computer Literacy, 2 nd edition Chapter 2

16 What are the most popular printer technologies? Today’s printers typically use ink jet or laser technology –An ink jet printer has nozzle-like print head that sprays ink to form characters and graphics Inexpensive choice of most home and small business applications Print high quality images produced by digital cameras and scanners –A laser printer uses same technology as photocopier More expensive Choice for business printers that produce high volumes Practical Computer Literacy, 2 nd edition Chapter 2

17 What are the most popular printer technologies? When selecting printer consider: –Print resolution –Print speed –Duty cycle –Operating costs –Memory –Duplex printing –Networkability Practical Computer Literacy, 2 nd edition Chapter 2

18 What are the options for specialized output devices? Upgrade computer’s speaker system for better sound quality A plotter is a special printer for line drawing such as blueprints A voice synthesizer converts digital text into audio output A computer projection device displays computer- generated images on large screen Practical Computer Literacy, 2 nd edition Chapter 2

19 How do I connect peripheral devices to my computer? Installation is a pathway to transmit data between device and computer –Wired connection may require only connecting wire to computer or may require adding expansion card to system unit –Most computers include a variety of built-in ports for connecting devices –Today, USB (universal serial bus) is the preferred way to connect devices –Wireless connection typically requires transceiver on both devices Infrared light Bluetooth Wi-Fi Practical Computer Literacy, 2 nd edition Chapter 2

20 How do I connect peripheral devices to my computer? Practical Computer Literacy, 2 nd edition Chapter 2

21 How do I connect peripheral devices to my computer? If peripheral device requires a port not on your computer, you install an expansion card Some devices require software, called device driver, to set up communications Practical Computer Literacy, 2 nd edition Chapter 2

22 How do I select components for my computer system? Guidelines for purchasing peripheral devices: –Consider the tasks for which you’ll use the computer –Determine your budget –Select a computer platform –Choose a desktop, notebook, or tablet configuration –Select processor type and speed –Select an operating system Practical Computer Literacy, 2 nd edition Chapter 2

23 How do I select components for my computer system? –Consider your storage needs –Consider RAM and video memory capacity –Evaluate the computer’s upgradeability –Select software –Select peripheral devices and accessories –Evaluate manufacturer and vendor support and warranty Practical Computer Literacy, 2 nd edition Chapter 2