The history behind NORAD's Santa tracker

Need to find Santa? Who you gonna call? How about NORAD?
Since 1955, the aerospace defense organization has been tracking Jolly Saint Nick as he darts around the globe to deliver presents before children wake up on Christmas morning. The tradition actually started by mistake. A department store ad posted in a local paper had provided a phone number where children could call up Santa. However, thanks to a misprint, children ended up calling NORAD instead. NORAD staff stayed up all night answering