Microsoft co-founder Bill Gates said the all-important "control-alt-delete" function was not supposed to exist in Windows. Courtesy / Reuters

The unique combination of three keys on the traditional QWERTY keyboard -- control, alt and delete -- is one of the most memorized gestures in the history of computing. But Microsoft (NASDAQ:MSFT) co-founder Bill Gates said the all-important function was not supposed to exist.

“It was a mistake,” Gates said at a recent Harvard fundraising campaign, which evoked several laughs from the audience. “We could have had a single button, but the guy who did the IBM keyboard design didn’t wanna give us our single button.”

You can thank David Bradley for “control-alt-delete.” One of the key designers on the first IBM PC, Bradley initially created the mechanism to trigger a “soft reboot” of the computer, choosing those particular keys since it would be impossible to press all three with one hand (on the original IBM PC keyboard). Since then, the “control-alt-delete” combination has been designed for different purposes relating to interrupting or facilitating certain functions on the computer. In DOS and the early years of Windows, “control-alt-delete” would trigger a reboot of the computer. After Windows 3.1, the command would invoke a task manager that would allow users to end Windows sessions, and in most Windows versions since then (including Windows XP and Windows 7), it will let a user log in or log out of their account.

“I may have invented [control-alt-delete], but Bill made it famous,” Bradley said in a famous 2011 interview sitting across from Gates, who did not look too amused by Bradley’s comment.

Besides “control-alt-delete,” Gates has been recently recognizing other Microsoft miscues in the past, including the company’s innovation issues and reluctance to join the smartphone race in its early going. The current chairman of the board at Microsoft is currently searching for a new CEO to replace Steve Ballmer, who announced his plans in August to retire within the year.

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