 The term "torpedo" was originally employed for a variety of devices, most of which would today be called mines.From about 1900, "torpedo" has been used strictly to designate a self-propelled underwater explosive device.While the battleship had evolved primarily around engagements between armored warships with large-calibre guns, the torpedo allowed small torpedo boats and other lighter surface vessels, submarines/submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large ships without the need of large guns, though sometimes at the risk of being hit by longer-range artillery fire.