Sail- or motor-driven vessel used for racing or recreation. The term is popularly applied to large recreational engine-powered boats; the sailboats known as yachts and used for racing are usually light and comparatively small. Until the mid-19th century, yachts were designed along the lines of naval craft such as schooners and cutters. Yacht design was greatly affected by the 1851 success of the America in the race that established the America's Cup. In the 20th century, notably after World War II, smaller racing and recreational craft became more common. See alsosailing.