chapter 2:input and output

Question 1

What is the difference between Input devices and Output devices?

Answer 1

Input devices: hardware used to convert data to a form can be processed by computer.
Output devices: hardware used to display or play back the results of computer processing.

Question 2

How many types does input have? What are they?

Answer 2

Input have 4 types:
* Data
* Software instructions
* User commands
* Response

Question 3

Name 7 input devices? describe each one.

Answer 3

1. Keyboard: most common input device.
2. Microphone: used to input sounds.
3. Mouse: pointing device.
4. Modems and routers: direct the input data.
5. Digital Cameras: input photos.
6. Webcam.
7. Scanners: copy printed images into computer and can stand-alone or part of printer.

Question 4

What is RSI?

Answer 4

RSI is Repetitive Strain Injury caused by using a keyboard a lot, but Ergonomic keyboards designed to reduce RSI.

Question 5

How does the microphone capture sound?

Answer 5

captures sounds in analog forms, but as we know computers can read only digital forms, this is why we use sound cards which is a circuit board processes sounds in multiple ways to make computer recognize the sounds.

Question 6

Name 3 pointing devices

Answer 6

Mouse: device send control signals to computer.
Touchpad
Touch screen

Question 7

How does the digital camera work?

Answer 7

Digital camera takes information from the lens and record it as pixels or small dots, and it has a memory to store pictures.

Question 8

How does computer read video?

Answer 8

The video must be in digital form created by the video adapter which is also compress files and it has its own memory called video memory (VRAM).

Question 9

How does the scanners work?

Answer 9

Most scanners have software called optical character recognition (OCR) to turn text into digital file.

Question 10

How many types of scanners?

Answer 10

There are three different types of scanners:
1. Sheetfed scanner: pull papers one at time.
2. Flatbed scanner: scan one paper.
3. Handheld scanner: useful to copy small papers.

Question 11

How many ways does the output device follow?

Answer 11

Output devices can be one of four ways:
* Text * Graphics * Video * Audio

Question 12

Give three examples for output devices?

Answer 12

Monitors, printers and speakers.

Question 13

What are monitors? And what are the types does it have?

Answer 13

Monitors are the most common soft copy output devices and it has two types:
* LCD (Liquid crystal display) and they consume low power and flat screens.
* CRT (Cathode ray tube) they are heavy and heat up easily.

Question 14

How can we output a video? What is DLP?

Answer 14

To outputting a video there are two devices:
* Data projectors which shows computer on projection screen. Digital light processing (DLP) projectors use millions of mirrors to create sharp images and we use DLP with large audiences like cinemas.
* Televisions especially high definition television (HDTV).

Question 15

What are the printers? And how many types of printers?

Answer 15

Printers are the most hard copy output devices and have two types: 1. Nonimpact: inkjet printers and laser printers. 2. Impact.

Question 16

What is the different between inkjet and laser in nonimpact printers?

Answer 16

Inkjet: make images by spraying a fine stream of ink.
Laser: heat fuses the toner to the paper to create the image.
We can find them both (inkjet and laser) in All-in-One printer versions.

Question 17

How does impact printer work?

Answer 17

Impact printers use hammers or pins to press the ink and they are noisy, but they still used in businesses to provide multi-part forms like invoices.

Question 18

How does the computer read text files and plays it as sounds?

Answer 18

By using Speech synthesis software.