Watercraft in the context of Personal flotation device

Maritime transport (or ocean transport) or more generally waterborne transport, is the transport of people (passengers) or goods (cargo) via waterways. Freight transport by watercraft has been widely used throughout recorded history, as it provides a higher-capacity mode of transportation for passengers and cargo than land transport, the latter typically being more costly per unit payload due to it being affected by terrain conditions and road/rail infrastructures. The advent of aviation during the 20th century has diminished the importance of sea travel for passengers, though it is still popular for short trips and pleasure cruises. Transport by watercraft is much cheaper than transport by aircraft or land vehicles (both road and rail), but is significantly slower for longer journeys and heavily dependent on adequate port facilities. Maritime transport accounts for roughly 80% of international trade, according to UNCTAD in 2020.

Maritime transport can be realized over any distance as long as there are connecting bodies of water that are navigable to boats, ships or barges such as oceans, lakes, rivers and canals. Shipping may be for commerce, recreation, or military purposes, and is an important aspect of logistics in human societies since early shipbuilding and river engineering were developed, leading to canal ages in various civilizations. While extensive inland shipping is less critical today, the major waterways of the world including many canals are still very important and are integral parts of worldwide economies. Particularly, especially any material can be moved by water; however, water transport becomes impractical when material delivery is time-critical such as various types of perishable produce. Still, water transport is highly cost effective with regular schedulable cargoes, such as trans-oceanic shipping of consumer products – and especially for heavy loads or bulk cargos, such as coal, coke, ores or grains. Arguably, the Industrial Revolution had its first impacts where cheap water transport by canal, navigations, or shipping by all types of watercraft on natural waterways supported cost-effective bulk transport.

A vehicle (from Latin vehiculum) is a machine designed for self-propulsion, usually to transport people, cargo, or both. The term "vehicle" typically refers to ground transport vehicles such as human-powered land vehicles (e.g. bicycles, tricycles, velomobiles), animal-powered transports (e.g. horse-drawn carriages/wagons, ox carts, dog sleds), motor vehicles (e.g. motorcycles, cars, trucks, buses, mobility scooters) and railed vehicles (trains, trams and monorails), but more broadly also includes cable transport (cable cars and elevators), watercraft (ships, boats and underwater vehicles), amphibious vehicles (e.g. screw-propelled vehicles, hovercraft, seaplanes), aircraft (airplanes, helicopters, gliders and aerostats) and space vehicles (spacecraft, spaceplanes and launch vehicles).

This article primarily concerns the more ubiquitous land vehicles, which can be broadly classified by the type of contact interface with the ground: wheels, tracks, rails or skis, as well as the non-contact technologies such as maglev. ISO 3833-1977 is the international standard for road vehicle types, terms and definitions.

Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow under atmospheric pressure, and can be thought of as artificial rivers.

In most cases, a canal has a series of dams and locks that create reservoirs of low speed current flow. These reservoirs are referred to as slack water levels, often just called levels. A canal can be called a navigation canal when it parallels a natural river and shares part of the latter's discharges and drainage basin, and leverages its resources by building dams and locks to increase and lengthen its stretches of slack water levels while staying in its valley.

A sailor, seaman, mariner, or seafarer is a person who works aboard a watercraft as part of its crew, and may work in any one of a number of different fields that are related to the operation and maintenance of a ship. While the term sailor has its etymological roots from sailing, that is a time when sailing ships were the main mode of transport at sea, it now refers to the personnel of all watercraft regardless of the type of vessel, boat or ship. It encompasses people who operate ships professionally, be it for a military (navy) or civilian (merchant navy) or for sports or recreation. In a navy, there may be further distinctions: sailor may refer to any member of the navy even if they are based on land, while seaman may refer to a specific enlisted rank. Additionally, fisherman are seen as a distinct type of sailor, that is those engaged in fishing.

Sailors have existed from the earliest periods in history as people used boats for purposes such as maritime transport. Professional sailors normally undertake training or other forms of education to develop their skills. Professional sailors are also governed by regulations, including the STCW Convention.

A harbor (American English), or harbour (Commonwealth English; see spelling differences), is a sheltered body of water where ships, boats, and barges can be moored. The term harbor is often used interchangeably with port, which is a man-made facility built for loading and unloading vessels and dropping off and picking up passengers. Harbors usually include one or more ports. Alexandria Port in Egypt, meanwhile, is an example of a port with two harbors.

Harbors may be natural or artificial. An artificial harbor can have deliberately constructed breakwaters, sea walls, or jetties or they can be constructed by dredging, which requires maintenance by further periodic dredging. An example of an artificial harbor is Long Beach Harbor, California, United States, which was an array of salt marshes and tidal flats too shallow for modern merchant ships before it was first dredged in the early 20th century. In contrast, a natural harbor is surrounded on several sides by land. Examples of natural harbors include Sydney Harbour, New South Wales, Australia, Halifax Harbour in Halifax, Nova Scotia, Canada, and Trincomalee Harbour in Sri Lanka.

Marine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or internal combustion engine driving a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems.

Human-powered paddles and oars, and later, sails were the first forms of marine propulsion. Rowed galleys, some equipped with sail, played an important early role in early human seafaring and warfare. The first advanced mechanical means of marine propulsion was the marine steam engine, introduced in the early 19th century. During the 20th century it was replaced by two-stroke or four-stroke diesel engines, outboard motors, and gas turbine engines on faster ships. Marine nuclear reactors, which appeared in the 1950s, produce steam to propel warships and icebreakers; commercial application, attempted late that decade, failed to catch on. Electric motors using battery packs have been used for propulsion on submarines and electric boats and have been proposed for energy-efficient propulsion.

Mechanical engineering is the study of physical machines and mechanisms that may involve force and movement. It is an engineering branch that combines engineering physics and mathematics principles with materials science, to design, analyze, manufacture, and maintain mechanical systems. It is one of the oldest and broadest of the engineering branches.

Mechanical engineering requires an understanding of core areas including mechanics, dynamics, thermodynamics, materials science, design, structural analysis, and electricity. In addition to these core principles, mechanical engineers use tools such as computer-aided design (CAD), computer-aided manufacturing (CAM), computer-aided engineering (CAE), and product lifecycle management to design and analyze manufacturing plants, industrial equipment and machinery, heating and cooling systems, transport systems, motor vehicles, aircraft, watercraft, robotics, medical devices, weapons, and others.

A harpoon is a long, spear-like projectile used in fishing, whaling, sealing, and other hunting to shoot, kill, and capture large fish or marine mammals such as seals, sea cows, and whales. It impales the target and secures it with barb or toggling claws, allowing the fishermen or hunters to use an attached rope or chain to pull and retrieve the animal. A harpoon can also be used as a ranged weapon against other watercraft in naval warfare.

Certain harpoons are made with different builds to perform better with the type of target. For example, the Inuit have short, fixed-foreshaft harpoons for hunting at breathing holes, while loose-shafted ones are made for throwing and remaining attached to the game.

A ship is a large watercraft designed for travel across the surface of a body of water, carrying cargo or passengers, or in support of specialized tasks such as warfare, oceanography and fishing. Ships are generally distinguished from boats, based on size, shape, load capacity and purpose. Ships have supported exploration, trade, warfare, migration, colonization, and science. Ship transport is responsible for the largest portion of world commerce.

The word ship has meant, depending on era and context, either simply a large vessel or specifically a full-rigged ship with three or more masts, each of which is square rigged.

Shipbuilding is the construction of ships and other floating vessels. In modern times, it normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to before recorded history.

Until recently, with the development of complex non-maritime technologies, a ship has often represented the most advanced structure that the society building it could produce. Some key industrial advances were developed to support shipbuilding, for instance the sawing of timbers by mechanical saws propelled by windmills in Dutch shipyards during the first half of the 17th century. The design process saw the early adoption of the logarithm (invented in 1615) to generate the curves used to produce the shape of a hull, especially when scaling up these curves accurately in the mould loft.

A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or informally to refer to remotely operated vehicles and robots, or to medium-sized or smaller vessels (such as the midget submarine and the wet sub). Submarines are referred to as boats rather than ships regardless of their size.

Although experimental submarines had been built earlier, submarine design took off during the 19th century, and submarines were adopted by several navies. They were first used widely during World War I (1914–1918), and are now used in many navies, large and small. Their military uses include: attacking enemy surface ships (merchant and military) or other submarines; aircraft carrier protection; blockade running; nuclear deterrence; stealth operations in denied areas when gathering intelligence and doing reconnaissance; denying or influencing enemy movements; conventional land attacks (for example, launching a cruise missile); and covert insertion of frogmen or special forces. Their civilian uses include: marine science; salvage; exploration; and facility inspection and maintenance. Submarines can be modified for specialized functions such as search-and-rescue missions and undersea cable repair. They are also used in the tourism industry and in undersea archaeology. Modern deep-diving submarines derive from the bathyscaphe, which evolved from the diving bell.

Amphibious warfare is a type of offensive military operation that today uses naval ships to project ground and air power onto a hostile or potentially hostile shore at a designated landing beach. Through history the operations were conducted using ship's boats as the primary method of delivering troops to shore. Since the Gallipoli Campaign, specialised watercraft were increasingly designed for landing troops, material and vehicles, including by landing craft and for insertion of commandos, by fast patrol boats, zodiacs (rigid inflatable boats) and from mini-submersibles. The term amphibious first emerged in the United Kingdom and the United States during the 1930s with introduction of vehicles such as Vickers-Carden-Loyd Light Amphibious Tank or the Landing Vehicle Tracked.

Amphibious warfare includes operations defined by their type, purpose, scale and means of execution. In the British Empire at the time these were called combined operations which were defined as "...operations where naval, military or air forces in any combination are co-operating with each other, working independently under their respective commanders, but with a common strategic object." All armed forces that employ troops with special training and equipment for conducting landings from naval vessels to shore agree to this definition. Since the 20th century, an amphibious landing of troops on a beachhead is acknowledged as the most complex of all military maneuvers. The undertaking requires an intricate coordination of numerous military specialties, including air power, naval gunfire, naval transport, logistical planning, specialized equipment, land warfare, tactics, and extensive training in the nuances of this maneuver for all personnel involved.

A catamaran (/ˌkætəməˈræn/) (informally, a "cat") is a watercraft with two parallel hulls of equal size. The wide distance between a catamaran's hulls imparts stability through resistance to rolling and overturning; no ballast is required. Catamarans typically have less hull volume, smaller displacement, and shallower draft (draught) than monohulls of comparable length. The two hulls combined also often have a smaller hydrodynamic resistance than comparable monohulls, requiring less propulsive power from either sails or motors. The catamaran's wider stance on the water can reduce both heeling and wave-induced motion, as compared with a monohull, and can give reduced wakes.

Catamarans were invented by the Austronesian peoples, and enabled their expansion to the islands of the Indian and Pacific Oceans.

Outrigger boats are various watercraft featuring one or more lateral support floats known as outriggers, which are fastened to one or both sides of the main hull. They can range from small dugout canoes to large plank-built vessels. Outrigger boats can also vary in their configuration, from the ancestral double-hull configuration (catamarans), to single-outrigger vessels prevalent in the Pacific Islands and Madagascar, to the double-outrigger vessels (trimarans) prevalent in Island Southeast Asia. They are traditionally fitted with Austronesian sails, like the crab claw sails and tanja sails, but in modern times are often fitted with petrol engines.

Unlike a single-hulled vessel, an outrigger or double-hull vessel generates stability as a result of the distance between its hulls rather than due to the shape of each individual hull. As such, the hulls of outrigger or double-hull boats are typically longer, narrower and more hydrodynamically efficient than those of single-hull vessels. Compared to other types of canoes, smaller outrigger canoes can be quite fast, yet are also capable of being paddled and sailed in rougher water. This paddling technique, however, differs greatly from kayaking or rowing. The paddle, or blade, used by the paddler is single sided, with either a straight or a double-bend shaft.

A lock is a device used for raising and lowering boats, ships and other watercraft between stretches of water of different levels on river and canal waterways. The distinguishing feature of a lock is a chamber in a permanently fixed position in which the water level can be varied. (In a caisson lock, a boat lift, or on a canal inclined plane, it is the chamber itself (usually then called a caisson) that rises and falls.

Locks are used to make a river more easily navigable, or to allow a canal to cross land that is not level. Over time, more and larger locks have been used in canals to allow a more direct route to be taken.

A thoroughfare is a primary passage or way of transport, whether by road on dry land or, by extension, via watercraft or aircraft. Originally, the word referred to a main road or open street which was frequented thoroughly.