AT keyboard
Alternatively
referred to as the 101-key keyboard, the AT keyboard is a US standard keyboard introduced in 1986 by IBM.
Unlike new keyboards the ATkeyboard does not include the additional three Microsoft
Windows keys now found on many IBM compatible
keyboards.
An AT keyboard may also be used to describe a keyboard that uses the AT (Din5) port as shown in the picture to the right. The Din5 Port is rarely used today since most computers use PS/2 and USB keyboards.
Also see: 104 keyboard, Keyboard definitions, Motherboard definitions, Port, PS/2, USB