What is a Primsoll line?

During the 19th century when ships were haphazardly overloaded and ultimately sunk, sacrificing both crew and cargo, guidlines had to be mandated. In 1875 a British politician named Samuel Plimsoll had an idea that a line be placed on the vessel in compliance with the appropriate load indicating a reference point on the hull in relation to the draft of the ship. This gave anyone that looked an immediate assessment of the safety of the vessel in relation to payload. This "load line" is still being used on watercrafts of all sizes today. Originally called the "Plimsoll Line", today it may be referred to as "Load Line" or "Water Line"