Geodetic circles are imaginary lines on the Earth's surface that represent the shortest path between two points. These circles are crucial in the field of geodesy, which studies the Earth's shape and gravitational field. Geodetic circles help in mapping and navigation by providing accurate measurements of distances and angles. One common type of geodetic circle is the great circle, which is formed by the intersection of a sphere with a plane that passes through its center. Great circles are essential for air and sea travel, as they allow for the most efficient routes over long distances.