"It was a mistake," Gates said. "We could have had a single button, but the guy who did the IBM keyboard design didn't want to give us our single button."
The man responsible for the combination is David Bradley, an engineer that worked on the original IBM computer.
The three-key command exists to this day in Windows 8 to lock a PC or run Task Manager.
Notable deaths of 2014 [PHOTOS]
FAMU hazing ringleader guilty of manslaughter