Black Friday (partying) Black Friday (partying) Mad Friday, Frantic Friday or Black Eye Friday is a nickname for the last Friday before Christmas in the United Kingdom. It is the most popular night for office and factories Christmas parties, which consequently makes it one of the busiest nights in the year for ambulances and the police. The term Black Friday originates as "jargon" used by NHS and Police, and has entered the popular lexicon. From 2013, the press began to use the term Mad Friday to avoid confusion with the American Black Friday in November, which was growing increasingly popular in the UK
Common year starting on Friday has only one Friday the 13th; The only Friday the 13th in this common year occurs in August. Leap years starting on Thursday share this characteristic, but also have another one in February. This is the only year type where the "n"th "Doomsday" (this year Sunday) is not in ISO week "n"; it is in ISO week "n"-1. In the (currently used) Gregorian calendar, the fourteen types of year (seven common, seven leap) repeat in a 400-year cycle (20871 weeks). Forty-three common years per cycle or exactly 10.75% start on a Friday. The 28-year sub-cycle does only span across century