Sir John Cohen, commonly known as Jack Cohen (1898-1979) was a British businessman who founded the Tesco supermarket chain. He was born in Whitechapel, the son of a tailor. He served in the Royal Air Force during the First World War, and at the end of the war in 1919 he began selling groceries from a stall in Hackney, in London's East End. He soon became the owner of a number of market stalls, and started a wholesale business. In 1924 he created the Tesco brand name from the initials of a tea supplier, T. E. Stockwell, and the first two letters of his surname. By 1939 Cohen owned a hundred Tesco shops. In 1948 he witnessed the American trend for self-service supermarkets, and opened the first such shop in Britain. Around 1949 Cohen moved to Finchley, where he bought a block of flats called Moss Hall Court.

He was married to Sarah. He had two daughters, Shirley and Irene. The first is now Dame Shirley Porter, a former leader of Westminster Council.