A "One-Design Class" refers to a category of sailing competitions where all boats are identical in design and specifications. This ensures that the race outcomes depend on the sailors' skills rather than differences in boat performance. Common examples of one-design classes include the Laser and J/24. In one-design racing, each boat is built to the same standards, promoting fairness and equality among competitors. This format is popular in both amateur and professional sailing, as it allows for a level playing field and encourages camaraderie among participants.