Tonnage: Tonnage measures the carrying capacity of a vessel in terms of weight. It helps determine fees, taxes, and regulatory compliance for ships entering ports.
Ballast: Ballast refers to heavy materials loaded onto a ship to improve stability by lowering its center of gravity. It counterbalances the weight distribution caused by varying cargo loads.
Stowage: Stowage involves arranging and securing cargo within a ship's hold (storage area). Proper stowage ensures efficient use of space while preventing damage during transport.