MAC OS – Unit A

1. Examining Input Devices Examining Output Devices MAC OS – Unit A Page: 6-7, 8-9

2. Examining Input Devices • Before a computera computer produce useful information, a user must get data into it. • This is done using Input Devices.

3. Types of Input Devices - Keyboard • One of the most frequently used input devices is the keyboard. • There are two kinds of keyboards: • Standard • Ergonomic: Ergonomic means that it has been designed to fit the natural placement of the hands

4. Ergonomic Keyboard Standard Keyboard

5. Types of Input Devices- Mouse • The pointing device that is known as the mouse controls the pointer. That is a small arrow on the screen. • Pointing devices are used to select and move graphical icons on the screen. A mouse has two buttons for clicking commands. • A mouse has a track wheel used for scrolling through the page. • Sometimes you have a track wheel that is used to move the arrow of the device without moving the mouse. • Notebook computers have a track pad. That is a touch-sensitive device that you drag your finger over to control the pointer.

6. Track ball Track pad

7. Types of Input Devices - Scanner • A scanner is an device that transfers the content on a piece of paper into memory. • Microphones are another types of input devices. • Input devices can be connected to the computer either with cables or wirelessly.

8. Microphone Scanner

9. Quick Quiz • Which of the following is a pointing device that allows you to control the pointer by moving the entire device around the desk ? • Mouse • Trackball • Trackpad • Pointing stick • Answer : Mouse

10. Types of Output Devices • Output is the result of processing input. • Output devices show you these results. • Types of output devices: monitor, printer, speakers, etc..

11. Monitor • Monitor displays output from the computer. • Figure A-9 , Page 9 shows two types of monitors: • Flat Panel Monitor: a light weight monitor that takes very little space on the desktop. Their images are created used LCD (Liquid Crystal Display) • CRT (Cathode Ray Tube): require more space to be placed on the desk • Apple’s Mac: combines the LCD monitor with other components into one unit.

12. Flat Panel CRT Apple’s Mac

13. Quick Quiz • What are the three types of monitors? • Flat panel monitor • CRT monitor • Apple’s Mac

14. Monitor Display • Monitor screen size is the diagonal measurement from one corner of the screen to the other. • Desktop computer range from 15” to 30” • Notebook computers range from 12” to 20” Monitors have graphic display which divides the screen into a matrix of dots called pixels. Resolution is the number of pixels the computer displays.

15. Monitor Display – Cont. • Dot pitch (Dp) measures the distance between pixels. A smaller dot pitch means a sharper image • To display graphics, a computer must have a graphics card, also called video display adapter or video card.

16. Printers • A printerproduces a paper copy, often called hard copy of the text or graphics processed by the computer. • There are three categories of printers: • Laser Printers: They produce high quality output quickly. A temporary laser image is transferred into paper with a powdery substance called toner. • Inkjet Printers: are usually used at home. They spray ink into the paper and produce good quality output • Dot Matrix Printers: transfer ink into the paper using striking a ribbon with pins. They are used for large papers.

17. Laser Printer Dot matrix Printer Inkjet Printer

18. Speakers • Speakers, are like speakers on sound system, allow you to hear sounds from the computer. • Speakers can be built in or external peripheral devices that would be attached to the computers.

19. Quick Quiz • In order to display graphics, a computer monitor needs : • Parallel port • Network card • Graphics card • Sound card • Answer: Graphics Card