Today in History, January 31

Apple Corps building at 3 Savile Row, site of the Let It Be rooftop concert.

Apple Corps building at 3 Savile Row, site of the Let It Be rooftop concert.

1969: The Beatles gave their last public performance — on the roof of their Apple Corps headquarters.

1933: The Lone Ranger made his radio debut.

2004: David Bradley, the man who wrote the computer code Ctrl+Alt+Delete (forces computers to restart when they will no longer follow other commands), retired from IBM after 28.5 years with the company.