Like many navies, the German Navy of the World War II era used letters and numbers to identify their smaller craft; generally, ships of destroyer size and smaller. (The first three classes of destroyers -- the Type 1934, Type 1934A, and Type 1936 -- destroyers Z-1 through Z-22 -- carried both a name and a number. It is my observation that in most reference works, they are known by their "number"; for example, I find many more references to the designation Z-1 rather than the name LEBERECHT MAASS.) Following is a list of initial letters, the German category these letters were derived from, and an "English translation" of that category. The latter is not an exact translation, but that of a generally accepted comparable vessel.
Source:
NAVIES OF THE SECOND WORLD WAR:
GERMAN SURFACE VESSELS 2
Lenton, H. T.
Macdonald and Co. (Publishers), Ltd.
London, England - 1966
pp. 156-159
| Initials | Category (German) | Equivalent (English) |
| AFP | Artillerie-Fahr-Prahme | Naval store ferry (gun) |
| FR | Fluss Räumboote | Esturial / river motor minesweeper |
| F | Geleitboote | Escort vessel |
| G | Geleitboote | Escort vessel |
| GR | Geleit Räumboote | Motor launch |
| HSK | Handels-Stör-Kreuzer | Armed merchant cruiser |
| K | Kanonenboote | Gunboat |
| KFK | Kriegsfischkutter | Naval drifter |
| KM | Kleine offensive Minenleger | Motor minelayer (small) |
| KS | Kleine Schnellboote | Motor torpedo boat (small) |
| KSB | Kriegssperrbrecher | Naval mine destructor |
| KT | Kriegstransporter | Naval transport |
| KT | Küsten Torpedoboote | Torpedo boat (coastal) |
| KUj | Kriegs U-Jäger | Naval anti-submarine trawler or corvette |
| LAT | Leichte-Artillerie-Träger | Auxiliary gunboat (light) |
| LS | Leichte Schnellboote | Motor torpedo boat (light) |
| M | Minensuchboote | Minesweeper and auxiliary minesweeper |
| MA | Minensuchboote ausländisch | Ex-enemy minesweeper |
| MAL | Marine-Artillerie-Leichter | Naval gun lighter |
| MFP | Marine-Fahr-Prahme | Naval store ferry |
| MNL | Marine-Nachschub-Leichter | Naval store lighter |
| MR | Mittlere Räumboote | Coastal motor minesweeper |
| MRS | Minen Räum(bootmutter) Schiffe | Depot ship for minesweepers |
| MZ | Mehrzwecke-Fahrzeuge | General purpose vessels |
| PA | none | Ex-enemy escort vessels |
| R | Räumboote | Motor minesweeper |
| RA | Räumboote ausländisch | Ex-enemy motor minesweeper |
| RD | none | Motor launch |
| S | Schnellboote | Motor torpedo boat |
| SA | Schnellboote ausländisch | Ex-enemy motor torpedo boat |
| SAT | Schwere-Artillerie-Träger | Auxiliary gunboats (heavy) |
| SB | Sperrbrecher | Mine destructors |
| SG | Schnelle Geleitboote | Fast escort vessels |
| T | Torpedoboote | Torpedo boat |
| TA | Torpedoboote ausländisch | Ex-enemy torpedo boat |
| TF | Torpedofangboote | Torpedo recovery boat |
| TFA | Torpedofangboote ausländisch | Ex-enemy torpedo recover boat |
| TS | Tragflachen Schnellboote | Hydrofoil craft |
| U | U-boote | Submarine |
| UA | U-boote | Ex-Turkish submarine |
| UB | U-boote | Ex-British submarine |
| UC | U-boote | Ex-Norwegian submarine |
| UD | U-boote | Ex-Dutch submarine |
| UF | U-boote | Ex-French submarine |
| UIT | U-boote | Ex-Italian submarine |
| Uj | U-Jäger | Sub-chaser |
| V | Versuchsboote | Experimental vessel |
| Vp | Vorpostenboote | Auxiliary patrol vessel (sea-going) |
| Vs | Vorposten-Sicherungsboote | Auxiliary patrol vessel (coastal) |
| VS | Versuchs-Schnellboote | Experimental motor torpedo boat |
| WBS | Wetter-Beobachtungs-Schiffe | Weather ship |
| Z | Zerstörer | Destroyer |
| ZF | Zerstörer französisch | Ex-French destroyer |
| ZG | Zerstörer griechisch | Ex-Greek destroyer |
| ZH | Zerstörer holländisch | Ex-Dutch destroyer |
| ZN | Zerstörer norwegisch | Ex-Norwegian destroyer |
An exception to the above were the coastal minesweepers (Kustenschutzboote), where the initial letters designated the geographical areas they were employed.
| Letters | Area employed |
| BO | Belgium (Ostend) |
| DB | Germany (Borkum) |
| DC | Germany (Cuxhaven) |
| DK | Germany (Kiel) |
| DPk | Germany (Pommeranian coast) |
| DW | Germany (Wilhelmshaven) |
| DWo | Germany (Western Baltic) |
| FB | France (Brest) |
| FBo | France (Boulogne) |
| FC | France (Calais) |
| FGi | France (Gironde) |
| FK | France (general) |
| FL | France (Lorient) |
| FN | France (St. Nazaire) |
| FO | France (Oleron) |
| FP | France (La Pallice) |
| FT | France (Toulon) |
| FV | France (general) |
| GA | Greenland (Attika) |
| GD | Greece (Dodecanese) |
| GK | Greece (Crete) |
| GL | Greece (general) |
| GM | Greece (general) |
| GP | Greece (Peloponese) |
| GPi | Greece (Piraeus) |
| HD | Netherlands (Den Helder) |
| HF | Netherlands (general) |
| HI | Netherlands (Ijmulden) |
| HJ | Netherlands (Ijmulden) |
| HOe | Netherlands (Den Oever) |
| HM | Netherlands (Maas) |
| HR | Netherlands (Rotterdam) |
| HS | Netherlands (Scheveningen) |
| HV | Netherlands (Flushing) |
| JA | Jutland / Aalborg |
| JBe | Jutland / Little Belt |
| KK | not listed |
| NB | Norway (Bergen) |
| NH | Norway (Hammerfest) |
| Ni | Norway (general) |
| NK | Norway (Christiansand) |
| NKj | Norway (Kirkennes) |
| NM | Norway (general) |
| NN | Norway (Narvik) |
| NO | Norway (Oslo) |
| NS | Norway (Stavanger) |
| NSa | Norway (Sandnessjoen) |
| NW | Norway (general) |
| RS | Russia (Sevastopol) |
| RT | Russia (Temryuk) |
| TJM | not listed |