Warships weren't the only sea weapons to be used during the war. A wide variety of other weapons were also employed including:

• Torpedoes. Launched from submarines, destroyers, or aircraft, torpedoes were effective against both surface and undersea ships. Numerous sizes and designs were used throughout the war, with improvements occurring regularly. Japanese torpedoes were far superior to Allied torpedoes, with the Japanese Type 93 being the largest torpedo used in the war.

• Mines. Several hundred thousand naval mines were placed over the course of the war. Four basic types of mines were used: acoustic mines, which were detonated by the sound of a ship's engine or propeller; contact mines, which exploded when struck; magnetic mines, which detonated when disturbed by a steel-hulled ship; and pressure mines, which reacted to changes in water pressure caused by a passing ship. Some mines had multiple capabilities.

• Depth charges. Developed and first used during World War I, depth charges were surface ships' primary method of defense against submarines. They typically consisted of a metal cylinder filled with explosives and fitted with a fuse that caused the canister to explode at a specific depth. Because surface ships often did not know exactly where or at what depth a submarine was, depth charges were often scattered in a fan pattern and set to go off at incremental depths. Depth charges were also dropped from submarine-hunting planes and blimps.