Input devices

Input devices

1. Barcode Reader

   • How? Uses laser to 'read' the barcode, reflected light is translated into binary code which then identifies the product and price from a database
   • EG Retail sales, library loans, postage package training, stock control, ID cards
   • Strength: accurate and fast /Limitation: data on barcode cant be edited

2. Digital Camera

   • How? pattern of light associated with the image is stored digitally on internal or external memory
   • EG personal use, engineers to communicate with clients, estate agents, number plate recognition
   • Strength: quick operating speeds and you can preview images images can be modified,can be attached to emails as a file / Limitations: image files can be 'memory heavy', quality of output may vary

3. Keyboard

   • How? keyboard translates key selections into digital format, it also contains a number of 'functions'
   • EG Enter data that must be copied from a document or audio source, directly input text, send instructions and commands to ccoputer based control systems
   • Strength: quick data entry, most common/ Limitations: easy to make mistakes, time consuming and can lead to RSI

4. MICR- Magnetic Ink Character Recognition

   • How? data printed in the form of specially designed characters using magnetised ink. This is read by an appropriately sensitive input device
   • EG cheques
   • Strength: really quick and accurate,humans and machines can make sense of the data, resistant to forgery/ Limitations: ink and reader are expensive cheques aren't really being used anymore

5. Smart Cards

   • How? Magnetic strip cards store encoded data about the cards user, chip and pin stores data on a small 'Mondex' chip
   • EG store personal details on debit and credit cards etc, chips can be used to store data on phone cards, travel tickets etc
   • Strength: Secure transactions, increasingly used/ Limitation: can be stolen.

6. Pointing Devices

   • How? The mouse ball sends positional information to the computer which is then translated into the movements of a pointer on the screen
     • EG communicate with GUI, select icons and activate commands, issue commands to the computer
     • Strength: GUI needs it, constant developments in the functions in these devices/ Limitation: experts use keyboard short cuts, hand to eye co-ordination required