Beacon:

Any artefact, built or floating, visible or recognisable from a distance, whether by land or sea, that is specifically intended to provide a signal or warning for any purpose not exclusive to navigation.

Navigational aid:

Any artefact set up, either in the sea or on land, whether built or floating, with the specific purpose, whether primary or otherwise, of assisting seamen in safe navigation. A navigational aid can be lit or unlit and may or may not have an audible signal. When floating, it is always moored in a fixed position.

Lighthouse:

A fully or partially enclosed built structure bearing a light that is used as a navigational aid and that is capable of admitting at least one person who can operate or maintain the light entirely from within.

Lightstructure:

A built structure bearing a light that is used as a navigational aid but is not capable of admitting one person to operate or maintain it entirely from within.

Daymark:

Any unlit, built navigational aid.

Lightship:

A floating lit navigational aid that is of sufficient size for it to accommodate at least one person.

LANBY (Large Automatic Navigational Buoy):

A large floating lit navigational aid that possesses telemetry systems, but is not of sufficient size for it to accommodate a person.

Lightfloat:

A floating lit navigational aid that has no telemetry installed and is not of sufficient size for it to accommodate a person.

Lightbuoy:

A small floating lit navigational aid.

Buoy:

A small floating unlit navigational aid that is typically can or cone shaped

Mark:

A small floating unlit navigational aid that is typically a pole with a marker mounted on top in a variety of geometrical shapes