What is the function of a rudder on a boat?

The rudder on a boat is primarily responsible for steering. By changing the angle of the rudder in the water, a boat can turn and navigate in various directions. When the rudder is displaced, it creates a difference in water pressure on either side of it, which causes the boat to turn toward the side with less pressure. This fundamental function is critical for maneuvering a vessel safely, especially in tight or crowded waterways.

Balancing the boat in the water involves factors such as weight distribution and buoyancy, which is not the primary role of the rudder. Increasing speed is typically achieved through the boat’s propulsion system, such as an engine or sails, rather than through the rudder. Maintaining weight distribution is a separate consideration related to the loading and stability of the hull, and is not influenced by the rudder's function.