There is no single "yacht type" of boat, rather many types that include sloops, yawls, catamarans, and ketches. The hundreds of different racing classes fall into three broad groups: one-design classes where very similar boats compete; handicap classes where dissimilar boats race, some with an advantageous time allowance; and rating classes where a variety of formulas take into account boat length, sail size, type of rig, and other factors. Sailboats originally had wooden hulls with sails made of sailcloth, a canvas commonly called duck. Today, however, fiberglass hulls and synthetic fabrics predominate, and rigid wing sails, which resemble aircraft wings, are used in place of a fabric sail when a high speed is desired (as in windsurfing or boats used to set speed-sailing records).
Especially popular are the 16–23 ft (4.88–7.01 m) one-design boats; these are mass-produced craft made from a single blueprint and intended for the sailor of modest means. Races between one-design boats are thought to be a particularly good test of a crew's ability, to which, rather than to design, any variation in speed must, at least in theory, be attributable.