Naming conventions for destroyers of the Royal Navy

The first Torpedo Boat Destroyer (TBD) in the Royal Navy was HMS Havock of 1893. From 1906, the term "torpedo boat destroyer" began to appear in the shortened form "destroyer" when referring to destroyer flotillas. There is no official Admiralty order pertaining to the change and the abbreviated term "TBD" is present in the Navy List up to 1919, even though destroyer was the term used in most official orders from 1917.

Up to 1913, names were allocated under no fixed system, leading to a heterogeneous array, although 2 groups were named systematically; after rivers and tribes (later the E and F classes, respectively). In 1913, with burgeoning numbers of TBDs, the Admiralty took the confusing situation in hand; Havock and her similar "27 knotter" sisters with 2 shafts were grouped as the A class, and similar groups of "30 knotter" TBDs were grouped as the B class (4 funneled ships), C class (3 funnels) and D class (2 funnels). Later classes of ships were grouped as the E to K classes, although there was no J class. These are ships that the observer would recognise as being the fore-runners of the modern destroyer, with the turtle back and low conning tower replaced by a forecastle and wheelhouse with a compass platform above.

The last class of ships built with mixed names were the Acasta or K class of the 1911 - 1912 program. From the L class of the 1912 - 1913 programme onwards, ships took the initial letter of their name from the class letter, although large classes such as the M, R and S were allocated more than one initial letter. Flotilla leaders were generally named after famed historical (and generally, naval) characters and vessels building for other countries that had been commandeered for the Royal Navy were not allocated into the letter system (e.g. ex-Turkish ships received "T" names and ex-Greek ships "M" names with a Greek mythology theme).

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