‘Billet’ indicates an appointment to (staffing of) a position – also called a 'slot' – like Squad Leader, Platoon Commander, Divisional Commander, Executive Officer, Supply Sergeant, etc. Confusingly, in some cases, the billet has the same designation as a rank, such as Hauptfeldwebel.

The equivalent Ranks given in English are neither completely World War II British nor American, and is not going to satisfy any specialist. (However a specialist would probably not be reading this anyway). Nearly all German officer ranks correspond to US Army ranks, although their terminology differs, a Generalmajor being the equivalent of a brigadier general. Modern US Army rank equivalents have some differences. There is one more enlisted rank (Command Sergeant Major), and one more Warrant Officer rank (Warrant Officer 3rd Class). US Army Warrant Officers are counted as officers, not enlisted men. In the German WWII Army, all ranks below 2nd Lieutenant were enlisted men.

The German Army divided officers billets into eight groups, depending on the function to be carried out. German wartime officer ranks were permanent, which often made it impossible for German officers to be promoted to the higher rank which their wartime billet would actually have warranted. For example, although a Captain normally staffed the billet of Company Commander, this was not always a rule. If there were not enough Captains then a senior member of a lower rank was assigned to that billet. Conversely, if there were too many of a higher rank than one or more might be assigned a lower ranking billet. Many Divisions were commanded by a Brigadier General - and even an occasional Colonel - instead of a Major General. Conversely, if a billet was particularly critical, a higher-ranking person might be assigned to that billet than would normally be the case. Skill was preferred to rank. Promotion was achieved by serving time. The function or billet filled as such was not a ground for promotion.

The enlisted men were divided into three billet groups: Senior Sergeants (Unteroffiziere mit Portepee) ("O" Group), Junior Sergeants (Unteroffiziere ohne Portepee) ("G" Group), and Other Ranks (Mannschaften) ("M" Group).

Enlisted members of the German Army had an ‘Occupation’ (Laufbahn), i.e. a career or field of specialty, like Infantry, Supply, Finance and so on. The occupation might be incorporated into the rank designation, such as Beschlagschmiedobergefreiter, a farrier (horseshoe smith) corporal; or even be used instead of the rank designations, such as Beschlagmeister, (‘Farrier Master’), who was an expert farrier sergeant.

The highest combat leader position held by an enlisted man was that of platoon leader. However, this usually applied only to the third and fourth platoons. All other combat command positions were held by officers. Sergeants and Warrant Officers were in charge of logistics and administration, freeing the officers for their primary function of leading men into combat. It was not unusual for senior enlisted men to become involved in combat when the need arose, although the German Army considered it a waste of skilled manpower to use these highly trained and experienced men for this purpose.

German Tables of Organization (KStN – Kriegsstärkenachweisungen) had many notes indicating which billets and specialist slots were to be filled with what ranks and specialists, listing which billets had priority over others, which could alternatively be filled by a person with specialized knowledge or skill, and which billets should by preference be filled with regular army personnel.

Although it was expected to have rank and billet corresponding to each other, this was far from the case. Specialist personnel was rare and many units were raised in a hurry, not having enough time to acquire all its correct personnel. And once a units entered combat, the chances of acquiring the exact, highly-skilled soldier for the correct position often became merely a matter of luck.

The German Wehrmacht also had a unique category of personnel within its ranks, namely the Wehrmachtbeamten, which can be loosely translated as Armed Forces Civil Servants or as Government Service Officials. They were found in administrative, legal, and technical service positions. They were civilians performing functions within the Armed Forces. They were members of the Armed Forces according to the Law of Land Warfare, but were not “soldiers” by the German definition. They wore uniforms identical with those of the Service branch they were serving with, albeit with different insignia. As officials, their authority extended only to their specialty field - unlike soldiers, whose authority extends to anyone whom the individual outranks. Beamten could not hold command. They were entitled to all the customs and courtesies associated with their rank/status, however. Their duties, at least at field and company level, could lead to armed encounters with enemy forces, and they were all armed with pistols.