Boaters call navigation rules – the basic laws governing the steering or sailing of a boat – “The Rules of the Road.” The Rules of the Road define the roles and responsibilities of vessel operators. If all operators obeyed these rules, most accidents could be avoided.
The Rules vary slightly depending on whether you are boating on inland or on international waters. As an example, when operating on inland waters, sound signals are signals of intent; when operating on international waters, they are signals of action.
The U.S. Aids to Navigation System is a system maintained by the U.S. Coast Guard, consisting of visual, audible, and electronic signals which are designed to assist the prudent mariner in the process of navigation. The aids to navigation system is not intended to identify every shoal or obstruction to navigation which exists in the navigable waters of the United States, but rather provides for reasonable marking of marine features as resources permit.
There is much more to the navigation rules than can be covered here.
More Information
Federal Navigation Regulations by subject
The Navigation Center for Excellence
USCG’s Division of Boating Safety
USCG Navigation Rules and Regulations Handbook
USCG Aids to Navigation System (ATON) Brochure