Black Friday is an informal name for the day following Thanksgiving Day in the United States, the fourth Thursday of November, which has been regarded as the beginning of the country's Christmas shopping season since 1952. Most major retailers open very early, as early as overnight hours, and offer promotional sales. Many non-retail employees and schools have both Thanksgiving and the following Friday off, which, along with the following regular weekend, makes it a four-day weekend, thereby increasing the number of potential shoppers.