Enhanced layout
Provided by the ASK Keyboard Dictionary
The Enhanced layout refers to the key arrangements that are de facto standard on current PC keyboards. It was developed from IBM's 122-key typewriter keyboard layout with some external influences such as from DEC's terminal keyboards. It was cemented by the Model M-based IBM Enhanced Keyboard from 1985. Following the success of the IBM Personal System/2 and adoption by my PC clone manufacturers, the Enhanced Keyboard's 101-key "ANSI" and 102-key "ISO" layouts both became the standard that most full-size or tenkeyless keyboards derive from albeit with the inclusion of Windows/GUI and menu keys that bring the full-size key count up to 104 and 105 keys for "ANSI" and "ISO" respectively.
