By medium long underwear, we usually mean boxer shorts with short fitted legs. Different lengths are available within boxer shorts; medium length means pant legs of a few inches that fall just below the groin. Boxer shorts became popular in the late 20th century. The two most popular men's underpants are boxer shorts and briefs, the major difference being that briefs do not have pant legs and boxer shorts do. Briefs are always tight around the body while boxer shorts can be loose. Boxer shorts are popular with the young while older people often opt for briefs.
