Submarines, warships capable of moving both above and below the surface

This is a unique ability among warships, and submarines are very different in design and appearance from surface ships. U-boats first became an important element of naval warfare in World War I (1914-1918), when Germany used them to destroy surface merchant shipping. In such attacks, submarines used their main weapon, self-propelled underwater missiles known as torpedoes. Submarine played a similar role on a larger scale during World War II (1939-1945), in both the Atlantic (on the German side) and Pacific (on the American side). In the 1960s, nuclear submarines became important strategic weapons platforms because they could remain submerged for months and launch long-range nuclear missiles without surfacing.

 Nuclear attack submarines, equipped with torpedoes, anti-ship missiles, and anti-submarine missiles, also became an important element of naval warfare. Below is a history of the development of submarines from the 17th century to the present. For the history of other warships, see Warships. 

 A vice would have to be used to shrink the sides to reduce its volume and allow it to sink. Bourne did not design his boat himself, and the construction of the first submarine is usually credited to the Dutch inventor Cornelius Drebbel (or Cornelius van Drebbel). Repeated attempts were made on the River Thames in England between 1620 and 1624, and they succeeded in steering the vessel to depths of 12 to 15 feet (4 to 5 meters) below the surface. It is said that King James I took one for short trips.

 Drebbel's submarine was similar to the one proposed by Bourne in that the outer hull was made of greased leather over a wooden frame. Oars projected from the sides and were sealed by tight-fitting leather flaps, providing propulsion both on the surface and underwater. Drebbel's first boat was followed by two larger boats built on the same principle.