A small fin is fitted at the bottom for stability. A washboard prevents waves from splashing water aboard. Seats are fitted with wheels which roll on runners or tracks. The Oars Oars are attached to the boat by adjustable outriggers and are hollow to reduce weight. There are eight boat classes, of which five are for sweep-oared rowing in which the rower uses one oar with both hands, and three are for sculling in which two oars are used, one in each hand.
Some classes carry a cox, who either sits in the stern or lies in the bow to steer the boat.
The letter M or W before a boat code denotes a Men's or Women's boat class. The repechage round is for losing crews in the heats, meaning that every crew which loses in a heat has a second chance before being eliminated. The draw is conducted round by round according to alternative and previously undisclosed systems. Gold, silver and bronze medals are awarded for the first three crews to cross the line in the A final. Programmes Men's Olympic rowing dates from 1896, women's from 1976 and lightweights from 1996.