What is the purpose of draft marks on ship hulls?

The purpose of draft marks on ship hulls is to indicate the waterline for proper loading. These markings show the distance from the waterline to the bottom of the hull at various points along the ship's length. By observing the draft marks, crew members can determine how much water the vessel displaces, which directly correlates to how much cargo it can safely carry without compromising its stability or structural integrity. Proper loading is essential for maintaining a vessel's buoyancy and maneuverability within safe operational limits. This function is critical for ensuring that the ship remains stable and seaworthy throughout its journey. The accurate reading of draft marks helps in managing ballast and cargo loading operations, which are vital for safe navigation.