Peripherals

Peripherals

1. Input technologies

   • Pointing devices
     • work with graphical user interface (GUI)
     • Electronic mose
     • Trackball
     • Pointing stick
     • Touch pad
   • Pen-based computing
     • have a pressure-sensitive layer under the LCD
   • Speech recognition systems
   • Optical scanning
     • Optical character recognition
   • Magnetic stripe

2. Output technologies

   • Video output
     • Video monitors
       • use a cathode ray tube
     • LCD
       • active matrix and dual scan
   • Prindted output
     • Injekt printers
       • spray ink onto a page
     • Laser printers
       • use an elecrtostatic process

3. Storage

   • Primary storage (main memory)
     • Semiconductor memory chips
       • Direct access memory or RAM
       • Random-access memory (read/write memory
         • each memory position can be read and changed
       • Read-only memory
         • for permanent storage
         • can be read but not erased or overwritten
       • Flash memory
   • Magnetic disks
     • Sequential access memory
     • Floppy disks
     • Hard disk devices
     • RAID
       • Fault-tolerant capacity
       • SANs
   • Magnetic Tape
     • long-term archival storage
     • backup storage
   • Optical disks
     • CD-ROM
       • cannot be erased
     • CD-R
     • CD-RW
     • DVD
       • DVD-ROM
       • DVD-RM
   • RFID
     • RFID reader
     • RFID chips
       • passive
       • active
     • privacy concerns
       • people may not be aware that they are tracked
       • possible to deduce identity through the purchased products