1. Name one computer application that requires high resolution?  How is screen resolution measured?  How is printer resolution measured?  What resolution is needed for satisfactory pictures on a screen?  What resolution is needed for "photo quality" printing on paper?
High resolution screens are needed for graphics applications such as those used for CAD or desktop publishing. Screen resolution is measured in pixels. The smaller the pixel size the higher the resolution. For instance, a screen resolution of 1024 x 820 pixels is much better than a screen resolution of 800 x 600 pixels. Printer resolution is measured in dpi (dots per inch). If there are a lot of dots per inch then the resolution is good. A dot matrix printer might only have a resolution of 80 dpi (use for receipts in a shop). A laser printer might have a resolution of 300 dpi (good for business letters. Magazine quality resolution is 800 dpi. Photos can be 80 dpi if they are shown on the screen. If photos are to be printed then they should be at the highest resolution of the printer itself – maybe 300 dpi.

2. What is an application that does not need high resolution?
A receipt in a supermarket does not need to be printed in high resolution. A dot matrix printer is fine for printing applications like this.

3. What is an LCD?
Liquid Crystal Display. This is a technology used for screens. It is commonly used for the screens of portable computers and also calculators. It is a common feature of the user interface of many electronic products such as digital cameras, ovens, microwaves, washing machines, air conditioning units and so on.

4. What is an advantage of using an LCD rather than a normal PC monitor? 
LCD screens are lighter, flatter and take less space. They use less power than CRT screens.

5. If LCD is better then why do we still use CRT?
People who require very high resolution and a fast refresh rate still prefer a CRT screen for their work. However, the quality of LCD screens is increasing quickly and already LCD screens are replacing CRTs in business environments. Also, the cost of an LCD is still much higher than the same size CRT screen

6. What is a flatbed plotter?
A flatbed plotter will draw diagrams with pens on a piece of paper that is fixed on a flat tablet. The plotter does use actual pens and creates lines by moving the pens over the page in the same way that we would create a drawing. This is different to the technology used by printers where pictures are made by joining dots together.

7. What is a drum plotter?
A drum plotter can print on very large pieces of paper. It does this by moving the page to be printed back and forwards over a drum. When the part of the page to be drawn on reaches the plotting zone on the drum then drawing is carried out by the plotter pens.

8. What is an application that uses a plotter?
Plotters are used for creating engineering designs and house plans.

9. What does it mean if your output device is offline?
If a device like a printer is offline then it can not be used (accessed) by the CPU. A printer that is switched off, unplugged or in error mode is offline.

10. What is voice recognition software?  See if you can find out about a program called "dragon speak".
Dragon Speak is a voice recognition application package. The software interprets voice information (received from a microphone) and then can do one of several things. It can carry out a command such as closing a window or starting a program. It can place the words you have spoken into a text document (no need for typing anymore).

11. What are some things to consider when deciding what output device is required?
We should consider the nature of the output before deciding on the output device. For instance, if we require house plans then we might choose both a large high resolution screen and a plotter as hardware peripherals for a CAD system. Cost is always a critical factor when choosing hardware. We want to pay the least amount that will give us the information that we need in the format we want.

12. Name three different types of printer?
Laser printers, inkjet printers and dot matrix printers are all in common usage today. Each type of printer has particular applications that it is suitable for. Cost, speed, resolution, reliability and the need for colour are factors to consider before purchasing a printer.

13. What is a use of dot matrix printers?
Dot matrix printers are very common in businesses that produce receipts for customers. The supermarket uses such technology.

14. What is an advantage of using an inkjet printer?
An inkjet printer will produce nice colour printing, even up to photo quality standard. Dot matrix and inexpensive (non-colour) laser printers can not do that.

15. What is a disadvantage of using an inkjet printer?
Inkjet printers are not as reliable as dot matrix printers and they are a lot more expensive to run.

16. Why would we choose to use a laser printer instead of an inkjet printer?
An inkjet printer, though able to produce good quality, is very much slower than a laser printer. A laser printer is able to produce a printed page for less money than an inkjet. Inkjet print cartridges are very expensive and do not last long. Quite often they jam up and sometimes they leak.

17. Describe a control system where the computer outputs a signal that switches on (or off) an actuator.  What does the IO interface do in such a system
A control system for an automatic door opener will have an actuator that opens and closes the door. The actuator is going to be controlled by a signal from a computer. A sensor on the door will provide input to the computer to tell it when to turn the actuator off because the door is completely closed or completely open. A feedback loop will provide feedback about the status of the actuator. The IO interface converts information from the sensors into digital for computer processing and also converts digital information from the computer into a signal that can be used to control the actuator.