Bearing

The horizontal direction of an object or point from an observer, expressed relative to a stated reference.

A true bearing is measured clockwise from true north, a magnetic or compass bearing from the corresponding north reference, and a relative bearing from the vessel’s heading or fore-and-aft line. Bearings are commonly written as three figures from 000 degrees to 359 degrees.

Bearings taken by compass, radar or visual instrument can be used to identify objects, monitor collision risk and obtain position lines. The reference must always be known, and compass error, instrument alignment and vessel motion allowed for where relevant.