Input and Output

Input Devices

1 Computer keyboards used to entering text into a word processing document

Advantages:

* They allow quick entry of original text

* They are robust devices

* They allow accurate entry of data

Disadvantages:

* Conventional keyboards can be difficult for people with disabilities to use

* They are not very quick for inputting data compared with direct data entry devices

* They take up more space than other input devices.

2 Numeric Keypads used specifically to enter numbers

Advantages:

* They are small so can be carried easily

* Many devices can be connected to the same computer at convections

* They are easy to cover up when entering a PIN

Disadvantages:

* It is difficult to enter text

* They can be too small for the numbers to be used effectively

* Possible repetition of keys

3 Pointing devices used in all applications which require selection from a graphical user interface.

Devices:

* Mouse in most PC’s

* Touchpad on laptop computer

* Tracker ball use by people with limited motor skills

Advantages:

* Easy to use as compare to keyboard

* Moves cursor around the screen faster than using keystrokes

* Take less space as compare to non pointing input device like keyboard.

Disadvantages:

* Data insertion through pointing devices is not possible or very difficult

* They are useless on command driven interfaces

* It is difficult to enter text.

4 Video digitisers is used to input video to a computer from a television or video camera

Advantages:

* Digital video is easily edited

* Ease of playback

* Video can be input to computer.

Disadvantages:

* Video files take up a great deal of memory

* Fast video capture cards may be needed to capture high quality video footage

* A powerful computer and graphics card is often needed to process video footage.

5 Remote Controls used to operate TVs, video players/recorders, DVD...