Anti-ship missiles are guided missiles designed to engage and destroy naval vessels. They are typically used by aircraft, ships, or submarines to attack enemy ships.

A Magnetic Anomaly Detector (MAD) is an instrument used to measure and detect variations in the Earth's magnetic field, primarily for locating submarines or other large metallic objects.

A sonobuoy is a expendable, self‑contained buoy equipped with acoustic or other sensors, deployed from aircraft to detect and track submarines or surface vessels.