Why was the day after Thanksgiving originally called 'Black Friday' in the retail industry?

Black Friday has become a global shopping phenomenon, but its origins are rooted in American retail history. Test your knowledge about how this massive shopping event got its name and evolved into the retail juggernaut it is today. Understanding the history of major retail events provides insights into consumer behavior patterns and retail strategy development.

This is a live public trivia poll on AIPolls.Net. Vote and see real-time results.

Because retailers traditionally moved from operating at a loss ('in the red') to making a profit ('in the black') on this day
Because of the chaos and traffic jams that occurred as shoppers flooded stores, causing police in Philadelphia to coin the term in the 1950s
Because it marked the day when retailers would offer their deepest discounts, 'blacking out' regular prices
Because it originated from a stock market crash that occurred on a Friday after Thanksgiving in the 1920s