Buoy

A floating marker or device used for navigation, mooring, measurement or another designated purpose.

Most navigational and mooring buoys are secured to a charted or defined position, while some scientific or tracking buoys drift. Shape, colour, topmark, light and sound can identify the function of an aid-to-navigation buoy under the applicable buoyage system.

A buoy may mark a channel, hazard, special area or mooring, but it does not necessarily show safe water on every side or remain exactly on station. Mariners should identify the buoy correctly, allow for its movement and verify their position with charts and other available information.