A boat is a watercraft of any size designed to float or plane, to work or travel on water. Small boats are typically found on inland (lakes) or in protected coastal areas. However, boats such as thewhaleboat were designed for operation from a ship in an offshore environment. In naval terms, a boat is a vessel small enough to be carried aboard another vessel (a ship). Another less restrictive definition is a vessel that can be lifted out of the water. Some definitions do not make a distinction in size, as 1000-foot bulk freighters on the Great Lakes are called oreboats. For reasons of naval tradition, submarines are usually referred to as 'boats' rather than 'ships', regardless of their size and shape.
Boats have a wide variety of shapes and sizes and construction methods due to their intended purpose, available materials or local traditions. Canoe type boats have a long history and various versions are used throughout the world for transportation, fishing or sport. Fishing boats vary widely in style partly to match local conditions. Pleasure boats include ski boats, pontoon boats, and sailboats. House boats may be used for vacationing or long-term housing. Small boats can provide transport or convey cargo (lightering) to and from large ships. Lifeboats have rescue and safety functions.