A ship /ʃɪp/ Audio (US) is a large vessel that floats on water. Ships are generally distinguished from boats based on size. Ships may be found on lakes, seas, and rivers and they allow for a variety of activities, such as the transport of persons or goods, fishing, entertainment, public safety, and warfare.
Ships and boats have developed alongside mankind. In major wars, and in day to day life, they have become an integral part of modern commercial and military systems. Fishing boats are used by millions of fishermen throughout the world. Military forces operate highly sophisticated vessels to transport and support forces ashore. Commercial vessels, nearly 35,000 in number, carried 7.4 billion tons of cargo in 2007.[1]
These vessels were also key in history's great explorations and scientific and technological development. Navigators such as Zheng He spread inventions as the compass and gunpowder. On one hand, ships have been used for colonization and the slave trade. On the other, they also have served scientific, cultural, and humanitarian needs.
As Thor Heyerdahl demonstrated with his tiny boat the Kon-Tiki, it is possible to achieve great things with a simple log raft. From Mesolithic canoes to today's powerful nuclear-powered aircraft carriers, ships tell the history of man.
[edit] Nomenclature
- For more details on this topic, see Glossary of nautical terms.
There is no universal rule to distinguish a ship from a boat. Usually, ships are larger than boats. A commonly used rule of thumb is that if one vessel can carry another, the larger of the two is a ship. As dinghies are common on sailing yachts as small as 35 feet (11 m), this rule of thumb is not foolproof.
A number of large vessels are traditionally referred to as boats. Submarines are a prime example. Other types of large vessels which are traditionally called boats are the Great Lakes freighter, the riverboat, and the ferryboat. Though large enough to carry their own boats and heavy cargoes, these vessels are designed for operation on inland or protected coastal waters. However referring to ships as 'boats' is more an American tradition than that followed in 'British' style Merchant Navies.
[edit] History
[edit] Prehistory and antiquity
The history of boats parallels the human adventure. The first known boats date back to the Neolithic Period, about 10,000 years ago. These early vessels had limited function: they could move on water, but that was it. They were used mainly for hunting and fishing. The oldest dugout canoes found by archaeologists were often cut from coniferous tree logs, using simple stone tools
About 5,000 years ago, people living near Kongens Lyngby in Denmark invented the segregated hull, which allowed the size of boats to gradually be increased. Boats soon developed into keel boats similar to today's wooden pleasure craft.
At about the same time, the first navigators began to use animal skins or woven fabrics as sails. Affixed to the top of a pole set vertically in a boat, these sails gave early ships great range. This allowed man to explore widely, allowing, for example the settlement of Oceania about 3,000 years ago.
The ancient Egyptians were perfectly at ease building sailboats. A remarkable example of their shipbuilding skills was the Khufu ship, a vessel 143 feet (44 m) in length entombed at the foot of the Great Pyramid of Giza around 2,500 BC and found intact in 1954. According to Herodotus, the Egyptians made the first circumnavigation of Africa around 600 BC.
The Phoenicians and Greeks gradually mastered navigation at sea aboard triremes, exploring and colonizing the Mediterranean via ship. Around 340 BC, the Greek navigator Pytheas of Massalia ventured from Greece to Western Europe and the British Isles.[2]
Before the introduction of the compass, celestial navigation was the main method for navigation at sea. In China, early versions of the magnetic compass were being developed and used in navigation between 1040 and 1117.[3] The true mariner's compass, using a pivoting needle in a dry box, was invented in Europe no later than 1300.[4][5]
[edit] Through the Renaissance
Until the Renaissance, navigational technology remained comparatively primitive. This absence of technology didn't prevent some civilizations from becoming sea powers. Examples include the maritime republics of Genoa and Venice, and the Byzantine navy. The Vikings used their knarrs to explore North America, trade in the Baltic Sea and plunder many of the coastal regions of Western Europe.
Towards the end of the fourteenth century, ships like the carrack began to develop towers on the bow and stern. These towers decreased the vessel's stability, and in the fifteenth century, caravels became more widely used. The towers were gradually replaced by the forecastle and sterncastle, as in the carrack Santa María of Christopher Columbus. This increased freeboard allowed another innovation: the freeing port, and the artillery associated with it.
In the sixteenth century, the use of freeboard and freeing ports become widespread on galleons. The English modified their vessels to maximize their firepower and demonstrated the effectiveness of their doctrine, in 1588, by defeating the Spanish Armada.
At this time, ships were developing in Asia in much the same way as Europe. Japan used defensive naval techniques in the Mongol invasions of Japan in 1281. It is likely that the Mongols of the time took advantage of both European and Asian shipbuilding techniques. In Japan, during the Sengoku era from the fifteenth to seventeenth century, the great struggle for feudal supremacy was fought, in part, by coastal fleets of several hundred boats, including the atakebune.
Fifty years before Christopher Columbus, Chinese navigator Zheng He traveled the world at the head of what was for the time a huge armada. The largest of his ships had nine masts, were 130 metres (430 ft) long and had a beam of 55 metres (180 ft). His fleet carried 30,000 men aboard 70 vessels, with the goal of bringing glory to the Chinese emperor.
[edit] Specialization and modernization
Parallel to the development of warships, ships in service of marine fishery and trade also developed in the period between antiquity and the Renaissance. Still primarily a coastal endeavor, fishing is largely practiced by individuals with little other money using small boats.
Maritime trade was driven by the development of shipping companies with significant financial resources. Canal barges, towed by draft animals on an adjacent towpath, contended with the railway up to and past the early days of the industrial revolution. Flat-bottomed and flexible scow boats also became widely used for transporting small cargoes. Mercantile trade went hand-in-hand with exploration, which is self-financing by the commercial benefits of exploration.
During the first half of the eighteenth century, the French Navy began to develop a new type of vessel, featuring seventy-four guns. This type of ship became the backbone of all European fighter fleets. These ships were 56 metres (180 ft) long and their construction required 2,800 oak trees and 40 kilometres (25 mi) of rope; they carried a crew of about 800 sailors and soldiers.
Ship designs stayed fairly unchanged until the late nineteenth century. The industrial revolution, new mechanical methods of propulsion, and the ability to construct ships from metal triggered an explosion in ship design. Factors including the quest for more efficient ships, the end of long running and wasteful maritime conflicts, and the increased financial capacity of industrial powers created an avalanche of more specialized boats and ships. Ships built for entirely new functions, such as firefighting, rescue, and research, also began to appear.
In light of this, classification of vessels by type or function can be difficult. Even using very broad functional classifications such as fishery, trade, military, and exploration fails to classify most of the old ships. This difficulty is increased by the fact that the terms such as sloop and frigate are used by old and new ships alike, and often the modern vessels sometimes have little in common with their predecessors.
[edit] Today
Boats and ships remain essential tools for international and domestic trade, national security and cultural purposes.
In 2007, the world's fleet included 34,882 commercial vessels with gross tonnage of more than 1,000 tons, totaling 1.04 billion tons. These ships carried 7.4 billion tons of cargo in 2006, a sum that grew by 8% over the previous year. In terms of tonnage, 37.5% of these ships are tankers, 35.8% are bulk carriers, 10.9% container ships and 10.3% general cargo ships.
In 2002, there were 1,240 warships operating in the world, not counting small vessels such as patrol boats. The United States accounted for 3 million tons worth of these vessels, Russia 1.35 million tons, the United Kingdom 504,660 tons and China 402,830 tons. The twentieth century saw many naval engagements during the two world wars, the Cold War, and the rise to power of naval forces of the two blocs. The world's major powers have recently used their naval power in cases such as the United Kingdom in the Falkland Islands and the United States in Iraq.
The size of the world's fishing fleet is more difficult to estimate. The largest of these are counted as commercial vessels, but the smallest are legion. Fishing vessels can be found in most seaside villages in the world. In 1997, the United Nations Food and Agriculture Organization identified 2.285 million fishing vessels worldwide. An estimated 132.2 million tonnes of fish and shellfish were produced in 2003. In 1990, 29 million fishermen were active in the world.
[edit] Types of ship
Ships are difficult to classify, mainly because there are so many criteria to base classification on. Classification systems exist that use criteria such as:
- The number of hulls, giving categories like monohull, catamaran, trimaran.
- The shape and size, giving categories like dinghy, keelboat, and icebreaker.
- The building materials used, giving steel, aluminum, wood, fiberglass, and plastic.
- The type of propulsion system used, giving human-propelled, mechanical, and sails.
- The epoch in which the vessel was used, triemes of Ancient Greece, Man ' o'wars eighteenth century).
- The geographic origin of the vessel, many vessels are associated with a particular region, such as the pinnace of Northern Europe, the gondolas of Venice, and the junks of China.
- The manufacturer, series, or class.
Another way to categorize ships and boats is based on their use, as described by Paulet and Presles.[6] This system includes military ships, commercial vessels, fishing boats, pleasure craft and competitive boats. In this section, ships are classified using the first four of those categories, and adding a section for lake and river boats, and one for vessels which fall outside these categories.
[edit] Commercial vessels
Commercial vessels or merchant ships can be divided into three broad categories: cargo ships, passenger ships, and special-purpose ships.[7] 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 in shipping 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, chemical tankers and LNG tankers.
Passenger ships range in size from small river ferries to giant cruise ships. This type of vessel includes ferries, which move passengers and vehicles on short trips; ocean liners, which carry passengers on one-way trips; and cruise ships, which typically transport passengers on round-trip voyages promoting leisure activities onboard and in the ports they visit.
Special-purpose vessels are not used for transport but are designed to perform other specific tasks. Examples include tugboats, pilot boats, rescue boats, cable ships, research vessels, survey vessels, and ice breakers.
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 officers and marine engineers on larger vessels. Special-purpose vessels often have specialized crew if necessary, for example scientists aboard research vessels. Commercial vessels are typically powered by a single propeller driven by a diesel engine.[citation needed] Vessels which operate at the higher end of the speed spectrum may use pump-jet engines or sometimes gas turbine engines.[citation needed]
 Two modern container ships in San Francisco |  A pilot boat near the port of Rotterdam |  The research vessel Pourquoi pas? at Brest, France |
[edit] Military vessels
There are many types of naval vessels currently and through history. Modern naval vessels can be broken down into three categories: warships, submarines, and support and auxiliary vessels.
Modern warships are generally divided into seven main categories, which are: aircraft carriers, cruisers, destroyers, frigates, corvettes, submarines and amphibious assault ships. Battleships encompass an eighth category, but are not in current service with any navy in the world.[8]
Most military submarines are either attack submarines or ballistic submarines. Until World War Two, 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 missiles and submarine-launched 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 bombs to nuclear weapons.
Most navies also include many types of support and auxiliary vessels, such as minesweepers, patrol boats, offshore patrol vessels, replenishment ships , and hospital ships which are designated medical treatment facilities.[9]
Naval vessels usually have fine hulls to maximize speed and maneuverability.[citation needed] They also usually have advanced electronics and communication systems, as well as weapons.
 American aircraft carrier Harry S. Truman and a replenishment ship |  American battleship USS Iowa fires an artillery salvo |  German Seehunde minesweepers |  French landing craft Rapière near Toulon |
[edit] Fishing vessels
Fishing vessels are a subset of commercial vessels, but generally small in size and often subject to different regulations and classification. They are distinguished by several criteria: the type of fish they catch, the fishing method used, geographical origin, and technical features such as rigging.
Commercial fishermen harvest many aquatic species, from tuna, cod, and salmon to shrimp, krill, lobster, clams, squid and crab, in various fisheries for these species.
Modern commercial fishermen use many methods. One is fishing by nets, 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 like long-line fishing and hand-line fishing). Another method is the use of fishing trap.
Fishing boats are generally small, often little more than 30 metres (98 ft)) but up to 100 metres (330 ft) for a large tuna or whaling ship. They feature holds large enough to keep a good-sized catch. The fish can then simply be stored on ice. Aboard a fish processing vessel, they can be made ready for market and sold more quickly once the ship makes port.
The simplest fishing boats have a small cabin with a saloon, a deck designed to accommodate fishing, and fishing equipment such as nets and lines. Trawlers have additional gear such as winches and arms. Other devices are used, such as a rear ramp on a stern-trawler, and a skiff on a tuna seiner.
 Fishing boat in Cap-Haïtien, Haïti |  A trawler at Saint-Nazaire |  An oyster boat at La Trinité-sur-Mer |  The Albatun Dos, a tuna boat at work near Victoria, Seychelles |
[edit] Inland and coastal boats
Many types of boats and ships 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 outcompeted in the carriage of high value items due to the higher speed, falling costs, and route flexibility of rail transport.
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.
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." Due to their additional beam, very large salties are never seen inland of the Saint Lawrence Seaway. Because the largest 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 account for more than half of the fleet.[citation needed] The St. Mary's Challenger, built in 1906 as the William P Snyder, is the oldest laker still working on the Lakes. 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.
 Riverboat Natchez on the Mississippi River |  Commuter boat on the Seine |
[edit] Other
The wide variety of vessels at work on the earth's waters defy a simple classification scheme. A representative few that fail to fit into the above categories include:
- Historical boats, frequently used as museum ships,
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