What does "course over ground" mean?

"Course over ground" refers to the actual direction that a vessel is moving across the surface of the earth. This measurement takes into account factors such as current, wind, and other forces that may affect the vessel's movement. Unlike "heading," which indicates the direction a vessel is pointed, the "course over ground" provides a more accurate representation of its true path relative to Earth's surface.

Understanding this concept is crucial for effective navigation, as it helps mariners adjust their navigational plans based on real-time conditions they encounter while underway. By monitoring course over ground, navigators can determine if they are on track towards their intended destination or if they need to make course corrections.