Ship transport is the process of transport by barge, boat, ship orsailboat over a sea, ocean, lake, canal or river. A watercraft is a vehicle designed to float on and move across (or under) water. The need for buoyancy unites watercraft, and makes the hull a dominant aspect of its construction, maintenance and appearance.
The first craft were probably types of canoes cut out from tree trunks. The colonization of Australia by Indigenous Australiansprovides indirect but conclusive evidence for the latest date for the invention of ocean-going craft. Early sea transport was accomplished with ships that were either rowed or used the wind for propulsion, or a combination of the two.
In the 1800s the first steam ships were developed, using a steam engine to drive a paddle wheel or propeller to move the ship. Thesteam was produced using wood or coal. Now most ships have anengine using a slightly refined type of petroleum called bunker fuel. Some specialized ships, such as submarines, use nuclear power to produce the steam. Recreational or educational craft still use wind power, while some smaller craft use internal combustion engines to drive one or more propellers, or in the case of jet boats, an inboard water jet. In shallow draft areas hovercraft are propelled by large pusher-prop fans.
Although slow, modern sea transport is a highly effective method of transporting large quantities of non-perishable goods. Transport by water is significantly less costly than air transport for trans-continental shipping; short sea shipping and ferries remain viable in coastal areas.
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