Marks and Spencer plc also known as M and S is a major British multinational retailer headquartered in the City of Westminster London. It is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index. It specialises in the selling of clothing home products and luxury food products. M and S was founded in 1884 by Michael Marks and Thomas Spencer in Leeds.Marks and Spencer plc also known as M and S is a major British multinational retailer headquartered in the City of Westminster London. It is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index. It specialises in the selling of clothing home products and luxury food products. M and S was founded in 1884 by Michael Marks and Thomas Spencer in Leeds.