A nuclear submarine is a type of military vessel powered by nuclear reactors. This allows it to operate underwater for extended periods without needing to surface for fuel. Nuclear submarines are designed for stealth and can carry out various missions, including surveillance, reconnaissance, and launching missiles. These submarines are equipped with advanced technology and can travel at high speeds while submerged. They play a crucial role in a nation's defense strategy, providing a powerful deterrent against potential threats. The ability to remain hidden underwater makes them a vital asset in modern naval warfare.