Black Friday is a colloquial term for the Friday following Thanksgiving Day in the United States. Many stores offer highly promoted sales on Black Friday and open very early (sometimes as early as midnight) or some time on Thanksgiving Day.

Black Friday has routinely been the busiest shopping day of the year in the United States since at least 2005.

The earliest evidence of the phrase Black Friday originated in Philadelphia, dating back to at least 1961, where it was used by police to describe the heavy pedestrian and vehicular traffic that would occur on the day after Thanksgiving. This usage dates to at least 1961.

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