IBM introduced the IBM PC keyboard in 1981. This became the standard keyboard in the PC industry and has 83 keys including ten function keys on the left-hand side of the keyboard. This keyboard did not have separate cursor control keys. IBM also used this keyboard for the PC XT. It is also known as the IBM XT keyboard. These keyboards only work with the old IBM PC or XT.

The IBM PC AT keyboard was introduced by IBM in 1984. This keyboard is similar to the IBM PC keyboard with a few changes. It has one additional key and status lights. It also has a larger ENTER key and the ESC key was moved to the numeric keypad. This also became a PC Industry standard.

Newer AT keyboards usually have a switch underneath that allow them to act as an AT or XT keyboard. This comes in handy when you are trying to use an AT keyboard on an older machine.

IBM introduced the enhanced 101 or IBM PS/2 keyboard in 1986. IBM attempted to streamline all its different keyboards into one. This keyboard has 101 keys and contains 12 function keys instead of 10 and saw the addition of separate cursor control keys. This also became a PC industry standard and is a very popular keyboard still in use by many PCs today.

The Windows keyboard is similar enhanced 101 keyboard with the addition of three keys which are specific to the operation of Windows 95 and Windows 98 Although you do not need this keyboard to run Windows 95/98, this keyboard specification is fast becoming an industry standard.