CNC machining a ship propeller - GIF

[Frank S]

The way I heard it was a ship was a vessel which can carry boats on it, a boat is a vessel wh9ich can be carried on a ship. Also strange is all submarines have been called boat. no matter their size. but they fit the descriptive narrative. Boat: a vessel for transport by water, constructed to provide buoyancy by excluding water and shaped to give stability and permit propulsion.
Ship: usually a large specialized, vessel for transport by water.