When is black Friday? The obvious answer is a literal one. It is the day after Thanksgiving, an American holiday when families gather to gorge on turkey and pumpkin pie, which this year falls on November 29th. Yet Black Friday is not simply a date, it is also an idea. The day traditionally marked the beginning of the festive shopping season, when people would start to stock up on Christmas presents. Today, it is the time of year during which everything goes on sale. And pinpointing when this begins is a much more difficult endeavour. In a bid to find an answer your columnist searched her inbox for the earliest Black Friday discount offered by a retailer. The missive came in early October.