The navy is the branch of a country's armed forces that conducts military operations at sea and along littoral zones. Navies protect shipping lanes, deter aggression, support ground forces, and provide humanitarian assistance after disasters. Service members in a navy are commonly called sailors and serve on a range of vessels as well as in aviation and specialized maritime units. For a general definition, see military branch.
Organization and common components
Modern navies are complex organizations combining ships, aircraft, submarines, and shore establishments. Many navies include a naval infantry or marine force that conducts amphibious operations and a naval aviation element for reconnaissance and strike missions. For the role of naval aviation, see naval aviation, and for marine units, see marine forces. Traditions, training and crests form part of naval culture; for cultural elements, see naval traditions.
Typical ship types
- Surface combatants: destroyers, frigates and corvettes that provide air defence, anti-submarine warfare and surface attack.
- Submarines: vessels designed for concealed operations under water for surveillance, deterrence and attack. See submarines.
- Aircraft carriers: large vessels that carry, launch and recover fixed-wing aircraft and helicopters to extend a navy's reach. See aircraft carriers.
- Support and auxiliary ships: replenishment, hospital, transport and mine countermeasure vessels that sustain operations at sea.
- Smaller craft: patrol boats, landing craft and specialized units for coastal security and special operations.
Roles, missions and importance
Navies perform a variety of peacetime and wartime missions. Common objectives include sea control and denial, protection of maritime trade, power projection ashore, nuclear deterrence (in the case of ballistic missile submarines), counter-piracy, disaster relief and maritime law enforcement. They also support diplomatic presence through port visits and multinational exercises. Operational priorities often reflect a state's strategic geography, economic dependencies and alliances.
History and development
The concept of a dedicated naval force dates back millennia, evolving from oared galleys and sailing fleets to steam-powered steel warships and, in the twentieth century, to aircraft carriers and nuclear submarines. Innovations in propulsion, weapons, sensors and communications continually reshape naval practice. The rise of naval aviation and submarine warfare in the early 1900s was followed by cold-war developments in anti-submarine tactics and the emergence of guided missiles and carrier strike groups.
Distinctions and notable facts
Navies are distinct from coast guards and merchant navies: coast guards focus on law enforcement and safety closer to shore, while merchant ships are civilian vessels engaged in commerce. Many modern navies operate in cooperation with allies and within multinational coalitions. For more on naval vessels in general, consult naval ships.




