AT keyboard

Also known as the 101-key keyboard, the AT keyboard is the US standard keyboard introduced in 1986 by IBM and is used with the IBM compatible computer. This is one of the most common keyboards used today and can easily be identified as a keyboard that does not include the extra three Windows keys introduced by Microsoft. An AT keyboard may also be used to describe a keyboard that uses the AT (Din5) port; this type of keyboard has been widely replaced by new standards such as PS/2 and USB keyboards. Below is an example of the AT interface found on the back computers.

AT Bus

Used for the IBM AT and compatible computers to transfer information from one component to the other at speeds of up to 16-bits of data at a time.