Chapter 3 Output and Storage

1. Chapter 3 Output and Storage Chapter 3 Output and Storage

2. Presentation Overview • Output • Display Devices • Printers • Audio Output • Storage Devices and Media • Magnetic Storage Devices and Media • Optical Storage Devices • Large Computer System Storage Devices

3. Output Types of Output • Text – characters and numbers used to create words, sentences, and paragraphs • Audio – any sound, including speech and music • Video – motion images, similar to those seen on a television or movie screen

4. Output Output Devices and Media • An output device is any hardware device that makes information available to a user. • Monitors, printers, televisions • An output medium is any material on which information is recorded. • Paper, plastic film, magnetic tape

5. Display Devices • The monitor is the most common soft-copy output mechanism. • It consists of a viewing screen and electronic parts that show images on a screen.

6. Display Devices The quality of monitor resolution is determined by the number of pixels. • A pixel is a single dot of anything displayed on a screen. • More pixels cause higher resolution and more detailed images.

7. Display Devices Monitor Performance • Monitor performance is determined by the • Video card – more VRAM means truer color and faster speed • Resolution – more pixels mean sharper graphics • Refresh rate – faster rate means less screen flicker

8. Display Devices Monitor Performance In the 800 x 600 pixels screen resolution (left), the desktop icons and the photo are larger then in the 1280 x 1024 pixels screen resolution (right).

9. Display Devices Monitor Ergonomics Correct positioning when using a monitor can reduce physical fatigue and discomfort.

10. Display Devices Other Display Devices • Wearable computers – devices such as headsets, eyeglasses, watches, etc., free • Television displays – HDTV provides a wider screen and higher resolution • Screen projector –projects images on a screen to large audiences

11. Printers What types of printers are available? • Impact printers Dot-matrix and line printers • Non-impact printers Ink-jet printers, laser printers, thermal printers, and plotters

12. Printers What types of printers are available? • Special purpose non-impact printers Photo, postage, label, and portable printers • Multifunction devices Facsimile machine

13. Printers • Portrait format’s (left) names comes from the fact that traditional portraits are taller than they are wide. • To represent a landscape(right), a wider-then-tall view is usually taken.

14. Printers • Before striking the ribbon, a dot-matrix printer extends the correct combination of pins to form a specific character. • The more pins the printer uses, the sharper the printed letters.

15. Printers An ink-jet printer produces output by spraying tiny droplets of ink onto the paper to form text and images.

16. Printers A laser printer produces output in a manner similar to that of a copy machine.

17. Other Types of Printers Thermal printers – use heat to transfer an impression onto paper Plotters – produce large-sized high-quality documents Photo printers – high-quality ink-jet printers designed to print photos Label printers – use heat to print on adhesive material Printers

18. Printers Other Types of Printers • Postage printers – weigh items, print postage, and meter postage accounts • Portable printers – battery-powered, small, lightweight • Facsimile machines – send and receive copies of documents through telephone lines

19. Audio Output Types of Audio Output • Built-in speakersproduce warning sounds. • Sound cardsproduce high-quality sound through external speakers for many applications that use music, voice, etc. • Speaker headsetsposition miniature speakers over the ears to minimize sound distraction. • Voice outputproduces synthesized human speech.

20. Storage Devices and Media • Information stored in a computer must be in a file. • The file extension indentifies the type of file.

21. Magnetic Storage Devices and Media • A storage device is hardware that houses a storage medium on which data is recorded. • A magnetic storage device is the most commonly used type of secondary storage. • Examples of magnetic storage devices include • Hard disks • Tape cartridges • USB flash drives

22. Magnetic Storage Devices and Media • A hard drive contains one or more hard disks on which data are stored. • When activated, read/write heads move in and out between the disks to record and/or read data.

23. Magnetic Storage Devices and Media • A flash drive plugs into the USB port of a computer. • Although they are only about the size of a car key, the newest flash drives can store up to 128 gigabytes of data.

24. Magnetic Storage Devices and Media • A tape cartridge contains magnetically coated tape housed in a small plastic container. • Tape cartridges are used with personal computers mainly for backing up the contents of a hard drive.

25. Optical Storage Devices Another type of secondary storage is the optical disc. Examples of optical storage devices include • Compact discs (CDs) • Digital versatile (or video) discs (DVDs)

26. Optical Storage Devices How do optical devices store data? • A high-intensity laser records data by burning tiny indentations called pits. • The flat, unburned areas on the disc are called lands.

27. Optical Storage Devices How do computers read data stored on optical devices? • A low-intensity laser reads the data by reflecting light through the bottom of the disc. • Pits and lands reflect light differently, so the computer can tell when the surface changes. • Pits and lands are both read as binary 0s. • The point at which a pit changes to a land (or vice versa) is read as a binary 1.

28. Optical Storage Devices CD Drive The CD is loaded printed side up, and the holes in the tray allow the laser to read the bottom surface of the disc once the tray is closed.

29. Optical Storage Devices An optical disc drive reads data stored on an optical disc.

30. Optical Storage Devices The strength of pits and lands indicates strings of binary 0s, while a change from a pit to a land (or vice versa) indicates a binary 1.

31. Optical Storage Devices Information is stored on a series of sectors along a single track that spirals outward from the center to the outer edge of the optical disc.

32. Optical Storage Devices • CD-Rs • Store information that is “burned” onto them using a CD-R drive • Can read and write data at speeds of up to 52X • CD-RWs (compact disc–rewritable) • Can be erased and rewritten multiple times • Require a CD-RW drive and special software • Can hold 650-700 MB of information

33. Optical Storage Devices • DVD-Rs • Can be recorded on only one time • Can be read by most commercial DVD-ROM players • Can hold up to 4.7 GB of data • DVD-RWs (digital versatile disc–rewriteable) • Allow data to be erased and recorded over many times without damaging the disc

34. Optical Storage Devices Types and Storage Capacities of Optical Discs

35. Optical Storage Devices Care Instructions for Optical Discs

36. Optical Storage Devices Steps for Cleaning an Optical Disc

37. Large Computer System Storage Devices • For large computers, magnetic disk storage consists of multiple disks contained in a plastic container called a disk pack. • When activated, read/write heads read or record on the disks by moving inward and outward between them.

38. Large Computer System Storage Devices Large computers may also use magnetic tape storage. • This type of storage uses magnetic reels of tape. • Data is stored and accessed sequentially along the full length of the tape.

39. Large Computer System Storage Devices A WORM (write once, read many) Disk • Used for very high-capacity storage • Can only be written once and cannot be overwritten • Mainly found in mainframe applications • Ideal for storing archival-type material • Usually only readable on the drive on which it was written

40. On the Horizon Based on the material presented in this chapter and your own experience, what do you think is on the horizon?