The modern destroyer evolved from an earlier type of ship called the 'torpedo boat destroyer'.

The invention of the steam turbine (as opposed to reciprocating piston engines) about the turn of the 20th century made compact, high speed vessels possible. The invention of the guided torpedo about the same time also made it possible for fast, maneuverable torpedo boats to threaten even the biggest battleships. Suddenly, guns and armor were not all that counted, and cheap, expendable fast torpedo boats could devastate a fleet of battlewagons, as the Japanese Imperial Navy demonstrated at Tsushima in 1905.

The response to the torpedo boat was the torpedo boat destroyer, a small, unarmored, fast ship which could keep up with torpedo boats, but overwhelm them with heavier guns. Torpedo boat destroyers could also carry torpedoes, so they also became a threat to battleships and cruisers, and the large ships now routinely were escorted by them.

Eventually, the term was shortened to "destroyer", and the class evolved into other roles: scout, picket, escort, cruiser, shore bombardment, antisubmarine work, anti-aircraft platform, and all-around utility work. The destroyer played the role the frigate did during the days of sail, a ship too small to engage a ship-of-the-line, or fight in "the line", but suitable for just about everything else.

Today, the battleship has disappeared and the cruiser is quickly going the same way (big targets, too expensive to lose). Even the torpedo boat has become a coastal raider with little blue water capability. Destroyers have evolved into all those missions, and are now undergoing specialization themselves. Modern destroyers are the size of WWII light cruisers.

Today, ther are basically three kinds of combatant ships: carriers, destroyers, and submarines.