large number of different types of racing shells. They are classified using: Number of rowers. In all forms of modern competition the number of rowers can be 1, 2, 4, or 8. In the 19th century, there were often races with 6, 10 and 12 rowers per boat. Position of coxswain. Boats are either coxless, bow-coxed (also called bowloaders), or stern-coxed. In coxless ("straight") boats, a steersman is responsible for steering by either use of a mechanism connecting one of his shoes by wire to the rudder—the swiveling of the shoe turns the rudder, or by using a hand controlled string, called a tiller rope, which is parallel to the gunwales or the boat, and controls the rudder in a similar fashion. Singles and doubles do not employ a rudder in competition; the oarsmen steer by increasing or decreasing pressure or length on one scull or the other. In competition, bow- and stern-coxed boats may race one another. Type of rowing. The rower(s) may each hold one oar (sweep rowing) or two oars (sculling). The shell then has one rigger or two riggers per rower. Although sculling and sweep boats are generally identical to each other (except having different riggers), they are referred to using different names: Sweep: straight pair (2-), coxed pair (2+), straight four (4-), coxed four (4+), eight (8+) (always coxed) Sculling: single (1x), double (2x), straight quad (4x); also, but not in world-class competition, coxed quad (4x+), and octuple (8x+) Steering Single, and double sculls are usually steered by the scullers pulling harder on one side or the other. In other boats, there is a rudder, controlled by the coxswain, if present, or by one of the crew. In the latter case, the rudder cable is attached to the toe of one of his shoes which can pivot about the ball of the foot, moving the cable left or right. The bowman may steer since he has the best vision when looking over his shoulder. On straighter courses, the strokesman may steer, since he can point the stern of the boat at some landmark at the start of the course. On international courses, landmarks for the steersmen, consisting of two aligned poles, may be provided. Damage The most commonly damaged piece of rowing equipment is the skeg, which is a metal or plastic fin that extends from the bottom of the boat to help maintain stability