In
navigation, a course (heading) is the intended path of a
vehicle over the surface of the Earth. For air travel, it is the
intended flight path of an airplane or the direction of a line drawn on
a chart representing the intended airplane path, expressed as the angle
measured from a specific reference datum clockwise from 0° through 360°
to the line. The reference can be
true north or
magnetic north and called true course or magnetic course
respectively. Course is customarily expressed in three digits, using
preliminary zeros if needed.
A Heading Device expresses the course of the vessel.
