(I’m posting this more for my reference than anything else)

It all started back in 1955, when an advertisement for Sears Roebuck & Co. urged children to call Santa Claus, but misprinted the telephone number and accidentally listed the hotline for the commander in chief of the Continental Air Defense Command’ (CONAD), NORAD’s predecessor. Colonel Harry Shoup, who was the director of operations at the time, decided to play along and enlisted his staff to participate in the monitoring of Santa’s whereabouts via “radar.” – Julia Angwin, Lead Editor of Wall Street Journal’s Digits