What type of azimuths do compasses measure when orienting a map?

Compasses measure magnetic azimuths when orienting a map. This is because a compass aligns itself with the Earth's magnetic field, allowing users to determine direction relative to magnetic north. This magnetic azimuth is essential for navigation on land or at sea, enabling precise alignment of a map to the physical terrain.

While true azimuths relate to geographic north, and grid azimuths are used in conjunction with grid systems on maps, a compass directly measures the magnetic azimuth which is more practical for immediate navigation. Arbitrary azimuths do not pertain to standard navigation practices and are not typically utilized in map orientation. Understanding magnetic azimuths is crucial for effective navigation and map reading, particularly in the field where compass use is common.