What does the term "Grid" refer to in navigation?

The term "Grid" in navigation specifically refers to a reference system used for map navigation. Grids are often used on nautical charts and topographic maps to provide a systematic way of identifying locations. They typically consist of intersecting lines that create a series of squares or rectangles, allowing navigators to determine precise coordinates for their current location or intended route. This system enhances accuracy in navigation and facilitates communication of locations among navigators and mapping services.

In contrast, the other concepts provided in the choices serve different purposes in navigation. The North Star relates to celestial navigation and is used by navigators for orientation in the night sky. The natural magnetic field describes the Earth's magnetic field and is important for compass-based navigation, while the angle of declination pertains to the deviation between true north and magnetic north, which affects how one reads a compass but does not relate directly to the concept of a grid in navigation.