In footwear and fashion, flip-flops are a kind of flat, backless sandal. They have a flat sole held on the foot by a u-shaped strap that passes between the first (big) and second toes and around either side of the foot, attached to the sole at three points, commonly known as the thong strap. They may have been developed out of traditional Japanese woven or wooden soled sandals ("i.e.", zori and setta) in Australia.