The destroyer class of ship came into existance as a weapon against the torpedo boat which itself came about as a cheap weapon against capital ships. The destroyer was in fact developed out of torpedo boat design. When opportunity provided, the destroyer could itself fulfill the mission of the torpedo boats and attack capital ships with torpedoes. Destroyers also were capable, being larger and more durable than torpedo boats, of serving as scout ships for the fleet. Eventually they became the general workhorses of the world’s navies. They were small, expendable, and supremely seaworthy.
Torpedo boats were powered at first by steam and, initially, very much resembled the MTBs/PTs/S-Boats of WWII in size and use. The term “motor torpedo boats,” is usually associated with later, internal combustion-engined types and their WWI predecessors.
The very first “torpedo boats” were actually steam-driven boats carried aboard larger ships and equipped to carry a Whitehead locomotive torpedo. Their use was probably thought of as analogous to the earlier “cutting-out” and fireship tactics against a force in harbor as I doubt they could have been much depended upon for open sea work. Their size, etc., points toward the later Motor Torpedo Boat.
True torpedo boats began to appear in the latter 1870s and were relatively small, steam driven vessels, usually armed with a single tube and some form of rapid fire weapon. Like the later MTBs they were ge- nerally looked upon as coastal weapons. As they grew in size and power they came to be perceived by the British Admiralty as a sea-going threat to the British Fleet particularly in the Channel and Baltic Sea. This led, first, to the Torpedo Gun Boat, a larger, more heavily-armed Torpedo Boat, and, ultimately, to the Torpedo Boat Destroyer – the direct ancestor of the Destroyer.
The term Torpedo Boat Destroyer became simply “Destroyer,” but the original sense still appears in the French and Italian designations “contre-torpilleur” and “cacciatorpediniere.”
Best current read for this: Lyon, David, ” The First Destroyers,” Annapolis, Maryland: Naval Institute Press, 1996. (For more Book selections, see our Book Review section.) If you’re interested in a video, A & E has The Great Ships – Destroyers (2001) and from U.S. News & World Report: The Destroyers (1992).