BattleshipA battleship is a large armored warship with a main battery consisting of large caliber guns. It dominated naval warfare in the late 19th and early 20th centuries. The term battleship came into use in the late 1880s to describe a type of ironclad warship, now referred to by historians as pre-dreadnought battleships. In 1906, the commissioning of into the United Kingdom's Royal Navy heralded a revolution in the field of battleship design.
SonarSonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. "Sonar" can refer to one of two types of technology: passive sonar means listening for the sound made by vessels; active sonar means emitting pulses of sounds and listening for echoes.
World War IWorld War I or the First World War, often abbreviated as WWI or WW1, known contemporaneously as the Great War, was a major global conflict lasting from 1914 to 1918. It was fought between two coalitions, the Allies and the Central Powers. Fighting took place throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. The first decade of the 20th century saw increasing diplomatic tension between the European great powers.
TorpedoA modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such a device was called an automotive, automobile, locomotive, or fish torpedo; colloquially a fish. The term torpedo originally applied to a variety of devices, most of which would today be called mines. From about 1900, torpedo has been used strictly to designate a self-propelled underwater explosive device.
Bletchley ParkBletchley Park is an English country house and estate in Bletchley, Milton Keynes (Buckinghamshire) that became the principal centre of Allied code-breaking during the Second World War. The mansion was constructed during the years following 1883 for the financier and politician Sir Herbert Leon in the Victorian Gothic, Tudor, and Dutch Baroque styles, on the site of older buildings of the same name. During World War II, the estate housed the Government Code and Cypher School (GC&CS), which regularly penetrated the secret communications of the Axis Powers - most importantly the German Enigma and Lorenz ciphers.
Winston ChurchillSir Winston Leonard Spencer Churchill (30 November 1874 - 24 January 1965) was a British statesman, soldier, and writer who served as Prime Minister of the United Kingdom twice, from 1940 to 1945 during the Second World War, and again from 1951 to 1955. Apart from two years between 1922 and 1924, he was a Member of Parliament (MP) from 1900 to 1964 and represented a total of five constituencies. Ideologically an economic liberal and imperialist, he was for most of his career a member of the Conservative Party, which he led from 1940 to 1955.
Enigma machineThe Enigma machine is a cipher device developed and used in the early- to mid-20th century to protect commercial, diplomatic, and military communication. It was employed extensively by Nazi Germany during World War II, in all branches of the German military. The Enigma machine was considered so secure that it was used to encipher the most top-secret messages. The Enigma has an electromechanical rotor mechanism that scrambles the 26 letters of the alphabet.
Unrestricted submarine warfareUnrestricted submarine warfare is a type of naval warfare in which submarines sink merchant ships such as freighters and tankers without warning, as opposed to attacks per prize rules (also known as "cruiser rules") that call for warships to search merchantmen and place crews in "a place of safety" (for which lifeboats do not qualify, except under particular circumstances) before sinking them, unless the ship shows "persistent refusal to stop ... or active resistance to visit or search".
Submarine snorkelA submarine snorkel is a device which allows a submarine to operate submerged while still taking in air from above the surface. British Royal Navy personnel often refer to it as the snort. A concept devised by Dutch engineers, it was widely used on German U-boats during the last year of World War II and known to them as a Schnorchel. Until the advent of nuclear power, submarines were designed to operate on the surface most of the time and submerge only for evasion or for daylight attacks.
ScuttlingA ship is scuttled when its crew deliberately sinks it, typically by deliberately opening holes in its hull. Scuttling may be performed to dispose of an abandoned, old, or captured vessel; to prevent the vessel from becoming a navigation hazard; as an act of self-destruction to prevent the ship from being captured by an enemy force (or, in the case of a vessel engaged in illegal activities, by the authorities); as a blockship to restrict navigation through a channel or within a harbor; to provide an artificial reef for divers and marine life; or to alter the flow of rivers.
