section_path: Types of ships/Naval vessels
section_name: Naval vessels
paragraph_text: Naval vessels
  
  Naval ships are diverse in types of vessel. They include: surface warships, submarines, and auxiliary ships.
  
  Modern warships are generally divided into seven main categories: aircraft carriers, cruisers, destroyers, frigates, corvettes, submarines and amphibious warfare ships. The distinctions among cruisers, destroyers, frigates, and corvettes are not codified; 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.
  
  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.
  
  Fast combat vessels such as cruisers and destroyers usually have fine hulls to maximize speed and maneuverability. They also usually have advanced marine electronics and communication systems, as well as weapons.