OCR AS Computing - Input, Output and Storage

OCR AS Computing - Input, Output and Storage

1. Input

   • Barcodes
   • Laser Scanners
   • Camera-based Readings
   • Computer Hardware
     • Keyboards
     • Mouse
     • Digital drawing pads
   • Fingerprint scanners
   • Iris scanners

2. Output

   • Monitors
     • LCDs
     • 3D
     • 4K
     • OLEDs
   • Printers
     • Laser printer
     • Inkjet printers
     • 3D printers
     • Impact printers
   • Multimedia projectors
   • Computer speakers

3. Storage

   • Primary Storage
     • RAM
       • Used to store programs and data that are currently being used
       • Volatile
       • Temporary and fast
     • ROM
       • Non-volatile
       • Holds information that needs to reside permanently in memory
         • Bootstrap sequence, which loads the OS into RAM
       • Very secure and can't be altered by the user
   • Secondary Storage
     • Retains all information even after the computer is turned off
     • Hard Disk
       • Can have very large capacity for storage, so suitable for desktops.
       • Very bulky, so not suited for mobility
       • If dropped, can be broken completely
       • Moving parts so access speed is slow
     • Optical Storage
       • Generally has little storage space in comparison
         • Blu-Rays have greatest storage of up to 50GB
       • Very mobile and protected from drops
         • Excessive scratches can damage
       • Cheap to produce
     • Solid State Storage
       • Fastest access speed
       • Relatively low storage space per mB than others
       • Silent, light and portable
       • Consumes less power
       • Resilient to damage
   • Virtual Storage
     • Storing data over the internet
     • Generally really expensive, but companies mostly offer a free allowance of data storage up to a limit
     • Data can be accessed anywhere with a valid internet collection