What is a boats draft?

The draft (or draught) of a ship's hull is the vertical distance between the waterline and the bottom of the hull. It's a way to help determine the minimum depth of water that a boat or ship can safely navigate, and it is a way of indirectly expressing the amount of water that the boat displaces. On ships and large boats you will see numbered hash marks on the hull. they refer to the number of feet, yards or meters down into the water the hull goes. The amount of cargo and passengers on board, and the type of water, salt or fresh, impact the draft significantly. A heavily laden ship in fresh water will sit much lower in the water than the same boat, empty, in salt water.