HARDWARE

HARDWARE

1. INPUT DEVICES

   • • Regular use of keyboards causes Repetitive Strain Injury (RIS). Disabled people cannt use keyboards
     • kEYBOARDS are used to input letters, numbers and symbols into the computer. They also have keys or special functions like Fn, Windows, Shift etc.
   • • Repetitive Strain Injury due to continuous use
     • MICE are pointing devices that have two buttins and a scroll wheel. It enables us to scroll through pages and documents
   • • Mics can be used for spying through social networks
     • MICROPHONES allows sound to be inputted into the computer system. External and built-in mics are used in VoIP softwares
   • • DIGITAL CAMERAS are used to capture pictures and film videos that can be imported into the computer for editing and storage
     • Pictures taken by cameras are only an interpretation of reality. Also images and videos can easily be manipulated
   • • SCANNERS can turn a physical image or paper into a digital one
     • Images are not always clear. The surface can be scratched and alter scans
   • • BARCODE READERS are used to scan barcodes, vertical bars on products, every time an item is scanned the inventory decreases by one
     • They can cause delays due to system failure Scratched bar codes cannot be decoded
   • • If the ink is not magnetised the reader cannot identify it
     • MAGNETIC INK CARD READER (MICR) read magnetic ink numbers at the bottom of cheques
   • • Can only read check boxes and MCQs
     • OPTICAL MARK READER can read pencil marking on printed paper and inputs it into the computer
   • • The screen may not be oriented making it difficult to draw
     • GRAPHICS TABLETS are used by designers to draw on a screen accurate images
   • • If the card is scratched the reader cannot identify the card holder
     • MAGNETIC STRIPE READER can read built-in magnetic stripes on debit/credit cards

2. OUTPUT DEVICES

   • • MONITORS display the graphical interface to the user
     • CRT monitors may not display good quality graphics
   • • PRINTERS are used to turn digitalised content into physical ones
     • Ink quality can alter what is being printed and give wrong information
   • • PLOTTERS can be used to produce A3+ prinouts such as CAD and CAM prints
     • Very noisy, expensive and require large spaces
   • • Buying toner and paper can be expensive. Also can contribute negatively to the atmosphere
     • LASER PRINTERS can print a large amount of HD printouts
   • • High Watts lights can be expensive
     • LIGHTS bulbs and LED'S are used to provide light
   • • INKJET PRINTERS print a number of quality printouts at a fast rate without noise
     • Toner is used up quickly and might be costly to refill
   • • PUMPS are used to push water or air up pipes
     • Can only work if connected to a motor
   • • SPEAKERS amplify sounds from computers
     • They do not always produce good sound quality. When used on high volumes, speakers often stop working
   • • PROJECTORS display images from the computer on a large flat surface
     • The resolution decreases as the image increases in size
   • • BUZZERS can provide noise to alert the user of something
     • If faulty then they cannot alarm users in crucial times ex. fire, burglary

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