True North

The direction along a meridian towards the geographic North Pole.

True north is the reference for true courses and bearings on most nautical charts and differs from magnetic north by local magnetic variation. Grid north on a projected chart or map can also differ slightly from true north except along selected lines.

A GNSS receiver can provide true-referenced course information through its datum and calculations, but a magnetic compass does not point true without correction. Directions should be labelled T, M or C where ambiguity could affect navigation.