Inland and coastal boats

Passenger ship of Köln-Düsseldorfer on the river Rhine

Many types of boats are designed for inland and coastal waterways. These are the vessels that trade upon the lakes, rivers and canals.

Barges are a prime example of inland vessels. Flat-bottomed boats built to transport heavy goods, most barges are not self-propelled and need to be moved by tugboats towing or towboats pushing them. Barges towed along canals by draft animals on an adjacent towpath contended with the railway in the early industrial revolution but were out competed in the carriage of high value items because of the higher speed, falling costs, and route flexibility of rail transport.

Lake freighters, also called lakers, are cargo vessels that ply the Great Lakes. The most well-known is the SS Edmund Fitzgerald, the latest major vessel to be wrecked on the Lakes. These vessels are traditionally called boats, not ships. Visiting ocean-going vessels are called "salties." Because of their additional beam, very large salties are never seen inland of the Saint Lawrence Seaway. Because the smallest of the Soo Locks is larger than any Seaway lock, salties that can pass through the Seaway may travel anywhere in the Great Lakes. Because of their deeper draft, salties may accept partial loads on the Great Lakes, "topping off" when they have exited the Seaway. Similarly, the largest lakers are confined to the Upper Lakes (Superior, Michigan, Huron, Erie) because they are too large to use the Seaway locks, beginning at the Welland Canal that bypasses the Niagara River.

Since the freshwater lakes are less corrosive to ships than the salt water of the oceans, lakers tend to last much longer than ocean freighters. Lakers older than 50 years are not unusual, and as of 2005, all were over 20 years of age.^[45]

The SS St. Marys Challenger, built in 1906 as the William P Snyder, was the oldest laker still working on the Lakes until its conversion into a barge starting in 2013. Similarly, the E.M. Ford, built in 1898 as the Presque Isle, was sailing the lakes 98 years later in 1996. As of 2007 the Ford was still afloat as a stationary transfer vessel at a riverside cement silo in Saginaw, Michigan.

Seagoing commercial vessels

Two modern container ships in San Francisco

Commercial vessels or merchant ships can be divided into four broad categories: fishing, cargo ships, passenger ships, and special-purpose ships.^[46] Modern commercial vessels are typically powered by a single propeller driven by a diesel or, less usually, gas turbine engine.^{[citation needed]}, but until the mid-19th century they were predominantly square sail rigged. The fastest vessels may use pump-jet engines.^{[citation needed]} Most commercial vessels have full hull-forms to maximize cargo capacity.^{[citation needed]} Hulls are usually made of steel, although aluminum can be used on faster craft, and fiberglass on the smallest service vessels.^{[citation needed]} Commercial vessels generally have a crew headed by a captain, with deck officersand marine engineers on larger vessels. Special-purpose vessels often have specialized crew if necessary, for example scientists aboard research vessels.

Fishing boats are generally small, often little more than 30 meters (98 ft) but up to 100 metres (330 ft) for a large tuna orwhaling ship. Aboard a fish processing vessel, the catch can be made ready for market and sold more quickly once the ship makes port. Special purpose vessels have special gear. For example, trawlers have winches and arms, stern-trawlers have a rear ramp, and tuna seiners have skiffs. In 2004, 85,800,000 tonnes (84,400,000 long tons; 94,600,000 short tons) of fish were caught in the marine capture fishery.^[47] Anchoveta represented the largest single catch at 10,700,000 tonnes (10,500,000 long tons; 11,800,000 short tons).^[47] That year, the top ten marine capture species also included Alaska pollock, Blue whiting, Skipjack tuna, Atlantic herring, Chub mackerel, Japanese anchovy, Chilean jack mackerel, Largehead hairtail, and Yellowfin tuna.^[47] Other species including salmon, shrimp, lobster, clams, squid and crab, are also commercially fished. Modern commercial fishermen use many methods. One is fishing bynets, such as purse seine, beach seine, lift nets, gillnets, or entangling nets. Another is trawling, including bottom trawl. Hooks and lines are used in methods likelong-line fishing and hand-line fishing. Another method is the use of fishing trap.

Cargo ships transport dry and liquid cargo. Dry cargo can be transported in bulk by bulk carriers, packed directly onto a general cargo ship in break-bulk, packed inintermodal containers as aboard a container ship, or driven aboard as in roll-on roll-off ships. Liquid cargo is generally carried in bulk aboard tankers, such as oil tankers which may include both crude and finished products of oil, chemical tankers which may also carry vegetable oils other than chemicals and LPG/LNG tankers, although smaller shipments may be carried on container ships in tank containers.

Passenger ships range in size from small river ferries to very large cruise ships. This type of vessel includes ferries, which move passengers and vehicles on short trips; ocean liners, which carry passengers from one place to another; and cruise ships, which carry passengers on voyages undertaken for pleasure, visiting several places and with leisure activities on board, often returning them to the port of embarkation. Riverboats and inland ferries are specially designed to carry passengers, cargo, or both in the challenging river environment. Rivers present special hazards to vessels. They usually have varying water flows that alternately lead to high speed water flows or protruding rock hazards. Changing siltation patterns may cause the sudden appearance of shoal waters, and often floating or sunken logs and trees (called snags) can endanger the hulls and propulsion of riverboats. Riverboats are generally of shallow draft, being broad of beam and rather square in plan, with a low freeboard and high topsides. Riverboats can survive with this type of configuration as they do not have to withstand the high winds or large waves that are seen on large lakes, seas, or oceans.

The Albatun Dos, a tuna boat at work near Victoria, Seychelles

Fishing vessels are a subset of commercial vessels, but generally small in size and often subject to different regulations and classification. They can be categorized by several criteria: architecture, the type of fish they catch, the fishing method used, geographical origin, and technical features such as rigging. As of 2004, the world's fishing fleet consisted of some 4 million vessels.^[41] Of these, 1.3 million were decked vessels with enclosed areas and the rest were open vessels.^[41] Most decked vessels were mechanized, but two-thirds of the open vessels were traditional craft propelled by sails and oars.^[41] More than 60% of all existing large fishing vessels^[48] were built in Japan, Peru, the Russian Federation, Spain or the United States of America.^[49]

Special purpose vessels

The weather ship MS Polarfront at sea.

A weather ship was a ship stationed in the ocean as a platform for surface and upper air meteorological observations for use in marine weather forecasting. Surface weather observations were taken hourly, and four radiosonde releases occurred daily.^[50] It was also meant to aid in search and rescue operations and to support transatlantic flights.^[50][51]Proposed as early as 1927 by the aviation community,^[52] the establishment of weather ships proved to be so useful during World War II that the International Civil Aviation Organization (ICAO) established a global network of weather ships in 1948, with 13 to be supplied by the United States.^[51] This number was eventually negotiated down to nine.^[53]

The weather ship crews were normally at sea for three weeks at a time, returning to port for 10-day stretches.^[50]Weather ship observations proved to be helpful in wind and wave studies, as they did not avoid weather systems like other ships tended to for safety reasons.^[54] They were also helpful in monitoring storms at sea, such as tropical cyclones.^[55] The removal of a weather ship became a negative factor in forecasts leading up to the Great Storm of 1987.^[56] Beginning in the 1970s, their role became largely superseded by weather buoys due to the ships' significant cost.^[57] The agreement of the use of weather ships by the international community ended in 1990. The last weather ship was Polarfront, known as weather station M ("Mike"), which was put out of operation on 1 January 2010. Weather observations from ships continue from a fleet of voluntary merchant vessels in routine commercial operation.

Naval vessels

American aircraft carrier USS Harry S. Truman and a replenishment ship

Naval vessels are those used by a navy for military purposes. There have been many types of naval vessel. Modern naval vessels can be broken down into three categories: surface warships, submarines, and support and auxiliary vessels.

Modern warships are generally divided into seven main categories: aircraft carriers, cruisers, destroyers, frigates, corvettes,submarines and amphibious assault ships. The distinction between cruisers, destroyers, frigates, and corvettes is not rigorous; the same vessel may be described differently in different navies. Battleships were used during the Second World War and occasionally since then (the last battleships were removed from the U.S. Naval Vessel Register in March 2006), but were made obsolete by the use of carrier-borne aircraft and guided missiles.^[58]

Most military submarines are either attack submarines or ballistic missile submarines. Until the end of World War II the primary role of the diesel/electric submarine was anti-ship warfare, inserting and removing covert agents and military forces, and intelligence-gathering. With the development of the homing torpedo, better sonar systems, and nuclear propulsion, submarines also became able to effectively hunt each other. The development of submarine-launched nuclear and cruise missiles gave submarines a substantial and long-ranged ability to attack both land and sea targets with a variety of weapons ranging from cluster munitions to nuclear weapons.

Most navies also include many types of support and auxiliary vessel, such as minesweepers, patrol boats, offshore patrol vessels, replenishment ships, and hospital ships which are designated medical treatment facilities.^[59]

Fast combat vessels such as cruisers and destroyers usually have fine hulls to maximize speed and maneuverability.^[60] They also usually have advanced marine electronics and communication systems, as well as weapons.