Marine vessel

Watercraft are water-borne vehicles including ships, boats, hovercraft and submarines. Watercraft usually have propulsive capability (whether by sail, oar or engine) and hence are distinct from a simple device that merely floats, such as a log raft.

Most watercraft would be described as either a ship or a boat. However, there are numerous craft which many people would consider neither a ship nor a boat, such as: surfboards (when used as a paddle board), underwater robots, seaplanes, jetskis and torpedoes.

Although ships are typically larger than boats, the distinction between those two categories is not one of size per se.

The term "watercraft" (unlike such terms as aircraft or spacecraft) is rarely used to describe any individual object: rather the term serves to unify the category that ranges from jet skis to aircraft carriers. Such a vessel may be used in saltwater and freshwater; for pleasure, recreation, physical exercise, commerce, transport or military missions.

Usually the purposes behind watercraft designs and skills are for seafaring education or leisure activities, fishing and resource extraction, transportation of cargo or passengers, and for conducting combat or salvage operations. In general, the purpose of a water vehicle identifies its utility with a maritime industry sub-sector.

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