Black Friday

The day after Thanksgiving is called Black Friday in the US. I thought everyone knew why Black Friday is called that, but I’ve recently realized that many people don’t. So allow me to enlighten those of you who don’t know, and probably don’t care, how Black Friday got its name.

Many retailers operate at a loss, or in the red, for most of the year and they depend on Christmas shoppers for much of their yearly profit. The Christmas shopping season begins on the Friday after Thanksgiving. That is the day that many retailers begin operating in the black.

The phrases in the red and in the black stem from the terms red ink to indicate a loss and black ink to indicate a profit. But where did those terms come from? Why is a loss called red ink, and why is a profit called black ink?

Before there were electronic calculators, there were mechanical adding machines. These adding machines were big and heavy and were filled with gears and cams and levers (I’m imagining here, as I’ve never actually taken one apart). The only operations they could do were addition and subtraction, but that was enough for most business owners, who needed to know how much money they had made or lost. The business owner would enter the amounts of money taken in that day, adding each amount to arrive at a sub-total, and then subtract the day’s expenses, to arrive at the total profit or loss.

Mechanical adding machines had an ink ribbon that enabled printing the numbers onto a spool of paper. The ribbon had black ink on the top half and red ink on the bottom half. Normally, numbers were printed in black ink. However, if the result of a calculation was a negative number, that number was printed in red ink so that it would stand out and not be mistaken for a positive number. So, a loss was printed in red ink, while a profit was printed in black ink. Though mechanical adding machines have been obsolete for half a century, the phrases red ink, black ink, in the red, and in the black, live on.