By now, we're all used to the phrase "Black Friday", as the day after Thanksgiving and the official start of the Christmas shopping season. In most cases, it's the busiest shopping day of the year. But, how did the name come about?

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According to Wikipedia:

"Black Friday is not an official holiday, but many non-retail employers also observe this day as a holiday along with Thanksgiving, giving their employees the day off, thereby increasing the number of potential shoppers.

The day's name originated in Philadelphia, where it originally was used to describe the heavy and disruptive pedestrian and vehicle traffic which would occur on the day after Thanksgiving. Use of the term started before 1961 and began to see broader use outside Philadelphia around 1975. Later an alternative explanation began to be offered: that "Black Friday" indicates the point at which retailers begin to turn a profit, or are "in the black".