Black Friday is not an official holiday, but many employees have the day off (with the exceptions of those employed in Retailing and Banking), which increases the number of potential shoppers. Retailers often decorate for the Christmas and holiday season weeks beforehand. Many retailers open extremely early, with most of the retailers typically opening at 5AM or even earlier. Some of the larger retailers (depending on the location) such as Sears, Macys and Walmarthave been reported to open as early as midnight on the start of Black Friday in localized areas and remain open for 24 hours throughout the day until midnight the following Saturday. Upon opening, retailers offer doorbuster deals and loss leaders to draw people to their stores. Although Black Friday, as the first shopping day after Thanksgiving, has served as the unofficial beginning of the Christmas season at least since the start of the modern Macy's Thanksgiving Day Parade in 1924, the term "Black Friday" has been traced back only to the 1960s.

The term "Black Friday" originated in Philadelphia in reference to the heavy traffic on that day (see Origin of the name "Black Friday" below). More recently, merchants and the media have used it instead to refer to the beginning of the period in which retailers go from being in the red to being in the black (i.e., turning a profit).