Large sailboats typically have a weighted keel that extends down into the water from the hull and works to prevent sideways movement. This allows sailboats to ‘skate’ or surf across the wind instead of being pushed downwind. The weight of the keel also serves to hold the boat upright against the force of the breeze. Some keels can be rotated up into the body of the boat to reduce draft (depth of the boat below the waterline) and allow them to be brought into more shallow waters.
