A naval ship (or naval vessel) is a military ship (or sometimes boat, depending on classification) that is used by a navy. Naval ships are differentiated from civilian ships by construction and purpose. Generally, naval ships are damage resilient and armed with weapon systems, though armament on troop transports is light or non-existent.
Naval ships designed primarily for naval warfare are termed warships, as opposed to support (auxiliary ships) or shipyard operations.
A patrol boat (also referred to as a patrol craft, patrol ship, or patrol vessel) is a relatively small naval vessel generally designed for coastal defence, border security, or law enforcement. However, large size patrol vessels are also operated by multiple navies and coastguards. There are many designs for patrol boats, and they generally range in size. They may be operated by a nation's navy, coast guard, police, or customs, and may be intended for marine ("blue water"), estuarine ("green water"), or river ("brown water") environments.
Per their name, patrol boats are primarily used to patrol a country's exclusive economic zone (EEZ), but they may also be used in other roles, such as anti-smuggling, anti-piracy, fishery patrols, immigration law enforcement, or search and rescue. Depending on the size, organization, and capabilities of a nation's armed forces, the importance of patrol boats may range from minor support vessels that are part of a coast guard, to flagships that make up a majority of a navy's fleet. Their small size and relatively low cost make them one of the most common naval vessels in the world.
A naval base, navy base, or military port is a military base, where warships and naval ships are docked when they have no mission at sea or need to restock. Ships may also undergo repairs. Some naval bases are temporary homes to aircraft that usually stay on ships but are undergoing maintenance while the ship is in port.
In the United States, the United States Department of the Navy's General Order No. 135 issued in 1911 as a formal guide to naval terminology described a naval station as "any establishment for building, manufacturing, docking, repair, supply, or training under control of the Navy. It may also include several establishments". A naval base, by contrast, was "a point from which naval operations may be conducted".
A navy, naval force, military maritime fleet, war navy, or maritime force is the branch of a state's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operations and related functions. It includes anything conducted by surface ships, amphibious ships, submarines, and seaborne aviation, as well as ancillary support, communications, training, and other fields.
The strategic offensive role of a navy is projection of force into areas beyond a country's shores (for example, to protect sea-lanes, deter or confront piracy, ferry troops, or attack other navies, ports, or shore installations). The strategic defensive purpose of a navy is to frustrate seaborne projection-of-force by enemies. The strategic task of a navy also may incorporate nuclear deterrence by use of submarine-launched ballistic missiles. Naval operations can be broadly divided between riverine and littoral applications (brown-water navy), open-ocean applications (blue-water navy), and something in between (green-water navy), although these distinctions are more about strategic scope than tactical or operational division.
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 warship or combatant ship is a naval ship that is used for naval warfare. Usually they belong to the navy branch of the armed forces of a nation, though they have also been operated by individuals, cooperatives and corporations. As well as being armed, warships are designed to withstand damage and are typically faster and more maneuverable than merchant ships. Unlike a merchant ship, which carries cargo, a warship typically carries only weapons, ammunition and supplies for its crew.
In wartime, the distinction between warships and merchant ships is often blurred. Until the 17th century it was common for merchant ships to be pressed into naval service, and not unusual for more than half of a fleet to be composed of merchant ships—there was not a large difference in construction, unlike the difference between a heavily armoured battleship and an ocean liner. Until the threat of piracy subsided in the 19th century, it was normal practice to arm larger merchant ships such as galleons. Warships have also often been used as troop carriers or supply ships, such as by the French Navy in the 18th century or the Imperial Japanese Navy during the Second World War. In war since the early 20th century, merchant ships were often armed and used as auxiliary warships, such as the Q-ships of the First World War and the armed merchant cruisers of the Second World War.
A naval ensign is an ensign (maritime flag) used by naval ships of various countries to denote their nationality. It can be the same or different from a country's civil ensign or state ensign.
It can also be known as a war ensign. A large version of a naval ensign that is flown on a warship's mast just before going into battle is called a battle ensign. An ensign differs from a jack, which is flown from a jackstaff at the bow of a vessel.
A merchant ship, merchant vessel, trading vessel, or merchantman is a watercraft that transports cargo or carries passengers for hire. This is in contrast to pleasure craft, which are used for personal recreation, and naval ships, which are used for military purposes.
They come in myriad sizes and shapes, from six-metre (20 ft) inflatable dive boats in Hawaii, to 5,000-passenger and more casino vessels on the Mississippi River, to tugboats plying New York Harbor, to 300-metre (1,000 ft) oil tankers and container ships at major ports, to passenger-carrying submarines in the Caribbean.