USB (Universal Serial Bus)

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In the Old Days . . .

  • Mice and keyboards only connected to 
  • dedicated connectors or serial port.
  • Networking (as such) was only through 
  • serial com port.
  • Printers had their own connector.
  • Not much else!



USB

  • Defined by Intel and other industry leaders in early 1990s.
  • Ease of use was primary goal.
  • Four-wire interface.
  • USB was designed to standardize the connection of computer peripherals (including keyboards, pointing devices, digital cameras, printers, portable media players, disk drives and network adapters) to personal computers, both to communicate and to supply electric power.
  • A single USB port can be used to connect up to 127 peripheral devices, such as mice, modems, and keyboards.
  • USB also supports Plug-and-Play installation and hot plugging.



  • USB provides much higher data transfer speeds, with fewer wires!
  • USB is a standard for a wired connection between two electronic devices, including a mobile phone and a desktop computer.
  • The connection is made by a cable that has a connector at either end. One end, the one that plugs into the computer, is the same across all USB cables while the one that plugs into the mobile device can be of various types such as miniUSB, microUSB or a proprietary connector.



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