This red jersey cardigan is a knitted sweater that you can fasten at the front with buttons. The Red School Cardigan is a sweater that opens in front. Your cardigan might have pearl buttons and pockets. Unlike a sweater that you pull on over your head, a cardigan is shrugged on over the shoulders and buttons, up the front — or is worn open, with no fasteners at all. A cardigan is a knitted sweater that you can fasten at the front with buttons.