The game takes place at sea, during World War II, where the player, an American captain, commands allied fores against opponents. The game also features a multiplayer mode where players can battle rival players.
There are several different playable ships. These include battleships, aircraft carriers, submarines, destroyers, battlecruisers, cruisers, PT boats, repair ships, cargo ships, landing craft and minelayers. Every ship has a special move that can be triggered during tactical battle.
Source: Wikipedia, "Steel Horizon", available under the CC-BY-SA License.