1. Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill Technology Education Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

2. McGraw-Hill Technology Education Chapter 1; Lesson B Interacting with Your Computer

3. 1B-3 The Keyboard The most common input device –Must be proficient with keyboard –Skill is called keyboarding –Standard keyboard layout based on IBM

4. 1B-4 The Keyboard Alphanumeric keys –Keys that produce letters and numbers –Caps lock and enter are included –Keys arrangement referred to as QWERTY

5. 1B-5 The Keyboard The modifier keys –Shift Alt and Ctrl –Provide additional functionality to keys –Ctrl and alt create shortcut keys

6. 1B-6 The Keyboard Numeric keypad –Located on the right –Laid out in 10-key arrangement –Number lock converts to a directional pad

7. 1B-7 The Keyboard Function keys –12 keys at the top of the keyboard –Use differs between applications –F1 typically provides help

8. 1B-8 The Keyboard Movement keys –Keys between alpha and number pad –Movement without using the mouse

9. 1B-9 The Mouse All modern computers have a variant Allows users to select objects –Pointer moved by the mouse Mechanical mouse –Rubber ball determines direction and speed –The ball often requires cleaning

10. 1B-10 The Mouse Optical mouse –Light shown onto mouse pad –Reflection determines speed and direction –Requires little maintenance

11. 1B-11 Variants of the Mouse Trackballs –Upside down mouse –Hand rests on the ball –User moves the ball –Uses little desk space

12. 1B-12 Variants of the Mouse Track pads –Stationary pointing device –Small plastic rectangle –Finger moves across the pad –Pointer moves with the pointer –Popular on laptops

13. 1B-13 Variants of the Mouse Track point –Little joystick on the keyboard –Move pointer by moving the joystick

14. 1B-14 Devices for the hand Pen based input –Tablet PCs, PDA –Pen used to write data –Pen used as a pointer –Handwriting recognition –On screen keyboard

15. 1B-15 Devices for the hand Touch screens –Sensors determine where finger points –Sensors create an X,Y coordinate –Usually presents a menu to users –Found in cramped or dirty environments

16. 1B-16 Devices for the hand Game controllers –Enhances gaming experience –Provide custom input to the game –Modern controllers offer feedback –Joystick –Game pad

17. 1B-17 Optical input devices Allows the computer to see input Bar code readers –Converts bar codes to numbers UPC code –Computer find number in a database –Works by reflecting light Amount of reflected light indicates number

18. 1B-18 Optical input devices Image scanners –Converts printed media into electronic –Reflects light off of the image –Sensors read the intensity –Filters determine color depths

19. 1B-19 Optical input devices Optical character recognition (OCR) –Converts scanned text into editable text –Each letter is scanned –Letters are compared to known letters –Best match is entered into document –Rarely 100% accurate

20. 1B-20 Audiovisual input devices Microphones –Used to record speech –Speech recognition Will ‘understand’ human speech Allow dictation or control of computer Matches spoken sound to known phonemes Enters best match into document

21. 1B-21 Audiovisual input devices Digital cameras –Captures images electronically –No film is needed –Memory cards store the images –Used in a variety of professions

22. 1B-22 Audiovisual input devices Video cameras –Captures movies electronically –No film is needed –Simple image compression is used

23. 1B-23 Monitors Most common output device Connects to the video card Two basic types

24. 1B-24 Monitors Cathode Ray Tube (CRT) –Most common type of monitor –Electrons fired from the back –Electrons excite phosphor to glow –Phosphor is arranged in dots called pixels –Dot mask ensures proper pixel is lit

25. 1B-25 Monitors Liquid Crystal Display (LCD) –Also known as a flat panel –Commonly found on laptops –Desktop versions exist –Solve the problems of CRT –Fluorescent lights provide illumination

26. 1B-26 Monitors Passive matrix LCD –Pixels arranged in a grid –Pixels are activated indirectly Row and column are activated –Animation can be blurry

27. 1B-27 Monitors Active matrix LCD –Each pixel is activated directly –Pixels have 4 transistors One each for red, green, blue One for opaqueness –Transistors arranged in a thin film –Animation is crisp and clean

28. 1B-28 Monitors Specification Monitors impacts user effectiveness Monitors should have: –Crisp text –Clear graphics –Adjustable controls –Clear edges

29. 1B-29 Monitors Specification Size of monitor –Measured in inches –Measured diagonally –Actual size Distance from corner to corner –Viewable size Useable portion of the screen

30. 1B-30 Monitors Specification Resolution –Number of pixels on the screen –Higher number creates sharper images –Higher number creates smaller images

31. 1B-31 Monitors Specification Refresh rate –Number of time the screen is redrawn –Modern equipment sets this automatically –Improper settings can cause eyestrain

32. 1B-32 Monitors Specification Dot pitch –Distance between the same color dots –Ranges between.15 mm and.40 mm –Smaller creates a finer picture –Should be less than.22

33. 1B-33 Video Cards Device between the CPU and monitor Better cards result in better output Removes burden of drawing from CPU Have their own processor and RAM Modern cards have up to 512 MB RAM Capable of rendering 3D images

34. 1B-34 Sound Systems Integral part of the computer experience Capable of recording and playback

35. 1B-35 Sound Systems Sound card –Device between the CPU and speakers –Converts digital sounds to analog –Can be connected to several devices

36. 1B-36 Commonly Used Printers Impact printers –Generate output by striking the paper –Uses an inked ribbon Non-impact printers –Use methods other than force –Tend to be quiet and fast

37. 1B-37 Commonly Used Printers Dot matrix printers –Impact printer –Used to print to multi-sheet pages –Print head strikes inked ribbon –Line printers –Band printers –Speed measured in characters per second

38. 1B-38 Dot Matrix Print Head

39. 1B-39 Commonly Used Printers Ink-jet printers –Non-impact printer –Inexpensive home printer –Sprays ink onto paper –Speed measured in pages per minute –Quality expressed as dots per inch

40. 1B-40 Dots Per Inch

41. 1B-41 Commonly Used Printers Laser printer –Non-impact printer –Produces high-quality documents –Color or black and white –Print process Laser draws text on page Toner sticks to text Toner melted to page –Speed measured in pages per minute –Quality expressed as dots per inch

42. 1B-42 Comparing Printers Determine what you need Determine what you can spend Initial cost Cost of operating Image quality

43. Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill Technology Education Chapter 1; Lesson B End of Lesson