5. Discussion.

1. Do you have a computer?

2. For what purposes do you use it?

3. What is its configuration?

4. Do all your computer features satisfy you?

5. Would you like to change your computer hardware? Why?

6. What components would be sufficient for your studies? For entertainment?

7. You have been asked to come up with the specification of a new design studio for a large company that wants to produce multimedia training applications for their staff. Write down and explain your choices of hardware.

8. What extra hardware or equipment is required to produce digital sound and video?

Unit 2 What is Input?

In this unit you will read about main input devices: keyboard, pointing devices, terminals and multimedia input devices. After reading this unit you should aim to achieve these targets by answering the questions at the end of the unit. You should be able to: - outline main input devices; - define their purposes; - explain their advantages and disadvantages.

Everything we tell the computer is Input.

Types of Input

Data is the raw facts given to the computer.

Programs are the sets of instructions that direct the computer.

Commands are special codes or key words that the user inputs to perform a task, like RUN "ACCOUNTS". These can be selected from a menu of commands like "Open" on the File menu. They may also be chosen by clicking on a command button.

User response is the user's answer to the computer's question, such as choosing OK, YES, or NO or by typing in text, for example the name of a file.

The first input device we will look at is the Keyboard. The image used illustrates the various keys may not look like the keyboard you are using. Several variations are popular and special designs are used in some companies. The keyboards shown below put the function keys in different places. The Enter and Backspace keys are different shapes and sizes. One has arrow keys while the other doesn't. It's enough to confuse a person's fingers!!

The backslash key has at least 3 popular placements: at the end of the numbers row, above the Enter key, and beside the Enter key. We also have the new Windows keyboards which have two new keys. One pops up the Start Menu and the other displays the right-click context sensitive menu. Ergonomic keyboards even have a different shape, curved to fit the natural fall of the wrists.

The layout of the keys was borrowed from the typewriter with a number of new keys added.

Alphabet keys

The letters of the alphabet and some punctuation marks are in these three rows. The order of the keys is called QWERTY from the order of the keys on the top row.

This arrangement of the letters was inherited from the typewriter. It is not the most efficient layout. With the first typewriters, the typists had trouble with the mechanical keys jamming each other because the typists could strike the keys faster than the keys could get out of each others' way. So the letters were arranged to slow down the typists' speed. Now that electric typewriters and computer keyboards no longer have mechanical keys, a more efficient layout could be used. But so many people are familiar and skilled with the old way that it doesn't seem likely that the layout will change.

Arrow keys

These four keys are used to move the cursor on the screen. The up and down arrows move the cursor up or down one line. The left and right arrows move the cursor one character.

Enter

The Enter key is used in several ways. In word processing, it acts like the Return key on a typewriter by starting a new line. It is also used in place of a mouse click with buttons and drop-down menus.

Function keys

The Function keys are numbered F1, F2, F3,....F12. These are programmable keys. That is, programs can assign actions to these keys. So the same key might produce different results in different programs.

Some of the function keys are becoming more standardized as to what they do. For example, F1 is most often used to access the Help file for a program.