Reefing is a sailing technique used to reduce the area of a sail when wind conditions become too strong. This helps maintain control of the boat and prevents damage to the sails or the vessel itself. Sailors can reef their sails by folding or rolling part of the sail to decrease its surface area, allowing for safer navigation in rough weather. There are different methods of reefing, including single-line reefing and double-line reefing, which vary in complexity and effectiveness. Proper reefing is essential for ensuring the safety of both the crew and the boat, especially during storms or high winds.