Black Friday, as a shopping term for the day after Thanksgiving, began in the 1950s and early 1960s in Philadelphia, where police used “Black Friday” to describe the heavy traffic and crowded streets caused by post‑Thanksgiving shoppers and visitors arriving for the Army–Navy football game. The name spread to retailers and other U.S. cities over the following decades and became widely popular nationwide by the 1980s, when it was reinterpreted as the day many stores moved from operating “in the red” to “in the black” for the year.