Torpedo

A torpedo is a self-propelled weapon with an explosive warhead, launched above or below the water surface or in space, propelled underwater/through space towards a target, and designed to detonate either on contact with its target or in proximity to it.

Historically on Terra, it was called an automotive, automobile, locomotive or fish torpedo; colloquially called a fish. The term torpedo was originally employed for a variety of devices, most of which would today be called mines. From about 1900 CE, torpedo has been used strictly to designate an underwater self-propelled weapon. The original torpedo is a kind of fish: an electric ray.

While the battleship had evolved primarily around engagements between armored ships with large-caliber guns, the torpedo allowed torpedo boats and other lighter surface ships, submersibles, even ordinary fishing boats or frogmen, and later, aircraft, to destroy large armored ships without the need of large guns, though sometimes at the risk of being hit by longer-range shellfire.

As used by the Union Navy, torpedoes can be divided into lightweight and heavyweight autonomous homing classes. They may or may not have anti-detection (so-called 'stealth') features. They are launched from a variety of platforms.