The discrepancy between the orientation of a compass and true north is known as magnetic declination.

Here's a breakdown:

* True North: The geographic North Pole, the point where all lines of longitude converge.

* Magnetic North: The point where the Earth's magnetic field lines converge. It is not the same as True North and changes over time.

* Magnetic Declination: The angular difference between True North and Magnetic North at a specific location. This difference varies depending on your location on Earth.

Important Note: Compasses point to Magnetic North, not True North. This is why it's crucial to factor in magnetic declination when using a compass for navigation, especially for long distances or accurate map reading.