what is a submarine?

[VictoriaL]

i just need 1 to 2 paragrafs about it for school

[Ineedhelpreallybadly]

Holy god CJ. 1 or 2 paragraphs man xDD Jk.

[thedouglasc65]

A submarine is a watercraft that can operate independently underwater, as distinct from a submersible that has only limited underwater capability. The term submarine most commonly refers to large manned autonomous vessels, however historically or more casually, submarine can also refer to medium sized or smaller vessels. i hope it helps ..
take care!

[the_beautiful_e]

It's a plain that goes under water!

[andy l]

the ones with seamen inside?

[mistyforestcreek]

my fingers hurt already!

[reesemg2002]

a vessel that can be submerged and navigated under water, usually built for warfare and armed with torpedoes or guided missiles

[BillA]

hah

[Josh W]

its an under water boat and it goes vrooom

[FelixTeCat]

A submarine is a watercraft that can operate independently underwater, as distinct from a submersible that has only limited underwater capability. The term submarine most commonly refers to large manned autonomous vessels, however historically or more casually, submarine can also refer to medium sized or smaller vessels, (midget submarines, wet subs), Remotely Operated Vehicles or robots. The word submarine was originally an adjective meaning "under the sea", and so consequently other uses such as 'submarine engineering' or 'submarine cable' may not actually refer to submarines at all. Submarine was shortened from the term 'submarine boat'.

Submarines are referred to as "boats" for historical reasons because vessels deployed from a ship are referred to as boats. The first submarines were launched in such a manner. The English term U-Boat for a German submarine comes from the German word for submarine, `U-Boot`, itself an abbreviation for Unterseeboot ('undersea boat').

Although experimental submarines had been built before, submarine design took off during the 19th century. Submarines were first widely used in World War I, and feature in many large navies. Military usage ranges from attacking enemy ships or submarines, aircraft carrier protection, blockade running, ballistic missile submarines as part of a nuclear strike force, reconnaissance and covert insertion of special forces. Civilian uses for submarines include marine science, salvage, exploration and facility inspection/maintenance. Submarines can also be specialised to a function such as search and rescue, or undersea cable repair. Submarines can also be used in tourism and for academic research.

Submarines have one of the largest ranges in capabilities of any vessel, ranging from small autonomous or one- or two-man vessels operating for a few hours, to vessels which can remain submerged for 6 months such as the Russian Typhoon class. Submarines can work at greater depths than are survivable or practical for human divers. Modern deep diving submarines are derived from the bathyscaphe, which in turn was an evolution of the diving bell.

Most large submarines comprise a cylindrical body with conical ends and a vertical structure, usually located amidships, which houses communications and sensing devices as well as periscopes. In modern submarines this structure is the "sail" in American usage ("fin" in European usage). A "conning tower" was a feature of earlier designs: a separate pressure hull above the main body of the boat that allowed the use of shorter periscopes. There is a propeller (or pump jet) at the rear and various hydrodynamic control fins as well as ballast tanks. Smaller, deep diving and specialty submarines may deviate significantly from this traditional layout.