
Action 14f13, also called "Sonderbehandlung 14f13" and Aktion 14f13, was a campaign by Nazi Germany to terminate Nazi concentration camp prisoners. Also called invalid or prisoner euthanasia, the campaign culled the sick, elderly and those deemed no longer fit for work, from the rest of the prisoners in a selection process, after which they were killed. The Nazi campaign was in operation from 1941 to 1944 and later covered other groups of concentration camp prisoners.

Arbeit macht frei is a German phrase meaning "Work sets you free" or "Work makes one free". The slogan is known for appearing on the entrance of Auschwitz and other Nazi concentration camps.

Arbeitslager is a German language word which means labor camp. Under Nazism, the German government used forced labor extensively, starting in the 1930s but most especially during World War II. Another term was Zwangsarbeitslager.

Aufseherin [ˈaʊ̯fˌzeːəʁɪn] was the position title for a female guard in the Nazi concentration camps during World War II. Of the 50,000 guards who served in Nazi concentration camps, about 5,000 were women. In 1942, the first female guards arrived at Auschwitz and Majdanek from Ravensbrück. The year after, the Nazis began conscripting women because of a shortage of male guards. In the context of these camps, the German position title of Aufseherin translates to (female) "overseer" or "attendant". Later female guards were dispersed to Bolzano (1944–1945), Kaiserwald-Riga (1943–44), Mauthausen, Stutthof (1942–1945), Vaivara (1943–1944), Vught (1943–1944), and at Nazi concentration camps, subcamps, work camps, detention camps and other posts.

In German military history, Bandenbekämpfung, also Nazi security warfare, refers to the concept and military doctrine of countering resistance or insurrection in the rear area during wartime through extreme brutality. The doctrine provided a rationale for disregarding the established laws of war and for targeting of any number of groups, from armed guerrillas to the civilian population, as "bandits" or "members of gangs". As applied by the German Empire and later by Nazi Germany, it became instrumental in the mass crimes against humanity committed by the two regimes, including the Herero and Namaqua genocide and the Holocaust.

The Concentration Camps Inspectorate (CCI) or in German, IKL was the central SS administrative and managerial authority for the concentration camps of the Third Reich. Created by Theodor Eicke, it was originally known as the "General Inspection of the Enhanced SS-Totenkopfstandarten", after Eicke's position in the SS. It was later integrated into the SS Main Economic and Administrative Office as "Amt D".

The Disciplinary and Penal Code was first written for Dachau concentration camp and became the uniform code at all SS concentration camps in the Third Reich on January 1, 1934. Also known as the Strafkatalog, it detailed the regulations for prisoners. SS guards were instructed to report violations of the code to the commandant's office. The Concentration Camps Inspectorate was responsible for execution of the resulting punishment, which was carried out without verification of the allegations or any possibility of vindication.

Einsatzgruppen were Schutzstaffel (SS) paramilitary death squads of Nazi Germany that were responsible for mass killings, primarily by shooting, during World War II (1939–1945) in German-occupied Europe. The Einsatzgruppen had an integral role in the implementation of the so-called "Final Solution to the Jewish Question" in territories conquered by Nazi Germany, and were involved in the murder of much of the intelligentsia and cultural elite of Poland, including members of the Catholic priesthood. Almost all of the people they killed were civilians, beginning with the intelligentsia and swiftly progressing to Soviet political commissars, Jews, and Romani people, as well as actual or alleged partisans throughout Eastern Europe.

The Final Solution or the Final Solution to the Jewish Question was a Nazi plan for the genocide of Jews during World War II. The "Final Solution to the Jewish question" was the official code name for the murder of all Jews within reach, which was not restricted to the European continent. This policy of deliberate and systematic genocide starting across German-occupied Europe was formulated in procedural and geopolitical terms by Nazi leadership in January 1942 at the Wannsee Conference held near Berlin, and culminated in the Holocaust, which saw the killing of 90% of Polish Jews, and two-thirds of the Jewish population of Europe.

The Gemeinnützige Krankentransport GmbH listen (help·info) was a National Socialist subdivision of the Action T4 organization. The euphemistically named company transported sick and disabled people to the Nazi killing centers to be murdered under the Nazi eugenics program and was known for the gray buses it used. The many victims were murdered in sealed gas chambers with carbon monoxide gas supplied in metal gas cylinders, and fed through false spray heads appearing to be shower heads. The programme Aktion T4 was managed by Victor Brack, who was tried for his crimes at Nuremberg, and executed as a result. The operation was ordered by Adolf Hitler in early September 1939, and organized by Philip Bouhler and Karl Brandt of the Reich Chancellery.

The Generalplan Ost, abbreviated GPO, was the Nazi German government's plan for the genocide and ethnic cleansing on a vast scale, and colonization of Central and Eastern Europe by Germans. It was to be undertaken in territories occupied by Germany during World War II. The plan was attempted during the war, resulting indirectly and directly in the deaths of millions by shootings, starvation, disease, extermination through labor, and genocide. But its full implementation was not considered practicable during the major military operations, and was prevented by Germany's defeat.

The Hilfspolizei was a short-lived auxiliary police force in Nazi Germany in 1933; (2) a general term for various organizations subordinated to the Ordnungspolizei during WW2; (3) a term also used for various military and paramilitary units set up during World War II in German-occupied Europe.

"Jedem das Seine" is the literal German translation of the Latin phrase suum cuique, meaning "to each his own" or "to each what he deserves".

Judenfrei and judenrein are terms of Nazi origin to designate an area that has been "cleansed" of Jews during The Holocaust. While judenfrei refers merely to "freeing" an area of all of its Jewish inhabitants, the term judenrein has the stronger connotation that any trace of Jewish blood had been removed as an alleged impurity in the minds of the criminal perpetrators. These terms of racial discrimination and racial abuse are intrinsic to Nazi anti-Semitism and were used by the Nazis in Germany before World War II and in occupied countries such as Poland in 1939. Judenfrei describes the local Jewish population having been removed from a town, region, or country by forced evacuation during the Holocaust, though many Jews were hidden by local people. Removal methods included forced re-housing in Nazi ghettos especially in eastern Europe, and forced removal or Resettlement to the East by German troops, often to their deaths. Most Jews were identified from late 1941 by the Yellow badge as a result of pressure from Joseph Goebbels and Heinrich Himmler.

A Judenrat was a World War II administrative agency imposed by Nazi Germany on Jewish communities across occupied Europe, principally within the Nazi ghettos. The Germans required Jews to form a Judenrat in every community across the occupied territories.

Judenfrei and judenrein are terms of Nazi origin to designate an area that has been "cleansed" of Jews during The Holocaust. While judenfrei refers merely to "freeing" an area of all of its Jewish inhabitants, the term judenrein has the stronger connotation that any trace of Jewish blood had been removed as an alleged impurity in the minds of the criminal perpetrators. These terms of racial discrimination and racial abuse are intrinsic to Nazi anti-Semitism and were used by the Nazis in Germany before World War II and in occupied countries such as Poland in 1939. Judenfrei describes the local Jewish population having been removed from a town, region, or country by forced evacuation during the Holocaust, though many Jews were hidden by local people. Removal methods included forced re-housing in Nazi ghettos especially in eastern Europe, and forced removal or Resettlement to the East by German troops, often to their deaths. Most Jews were identified from late 1941 by the Yellow badge as a result of pressure from Joseph Goebbels and Heinrich Himmler.

A kapo or prisoner functionary was a prisoner in a Nazi camp who was assigned by the SS guards to supervise forced labor or carry out administrative tasks.

The phrase "life unworthy of life" was a Nazi designation for the segments of the populace which according to the Nazi regime had no right to live. Those individuals were targeted to be euthanized by the state, usually through the compulsion or deception of their caretakers. The term included people with serious medical problems and those considered grossly inferior according to the racial policy of Nazi Germany. This concept formed an important component of the ideology of Nazism and eventually helped lead to the Holocaust. It is similar to but more restrictive than the concept of Untermensch, subhumans, as not all "subhumans" were considered unworthy of life.

Nacht und Nebel, meaning Night and Fog, was a directive issued by Adolf Hitler on 7 December 1941 targeting political activists and resistance "helpers" in World War II, who were to be imprisoned, killed, or made to disappear, while the family and the population remained uncertain as to the fate or whereabouts of the Nazi state's alleged offender. Victims who disappeared in these clandestine actions were never heard from again.

"Never again" is a phrase or slogan which is associated with the Holocaust and other genocides. The phrase may originate from a 1927 poem by Yitzhak Lamdan which stated "Never again shall Masada fall!" In the context of genocide, the slogan was used by liberated prisoners at Buchenwald concentration camp to express anti-fascist sentiment. The exact meaning of the phrase is debated, including whether it should be used as a particularistic command to avert a second Holocaust of Jews or whether it is a universalist injunction to prevent all forms of genocide. It was adopted as a slogan by Meir Kahane's Jewish Defense League.

The Ordnungspolizei, abbreviated Orpo, meaning "Order Police", were the uniformed police force in Nazi Germany from 1936 to 1945. The Orpo organisation was absorbed into the Nazi monopoly on power after regional police jurisdiction was removed in favour of the central Nazi government. The Orpo was controlled, nominally by the Interior Ministry but its executive functions rested with the leadership of the SS until the end of World War II. Owing to their green uniforms, Orpo were also referred to as Grüne Polizei. The force was first established as a centralised organisation uniting the municipal, city, and rural uniformed police that had been organised on a state-by-state basis.

A prisoner functionary was a prisoner in a Nazi concentration camp who was assigned by the SS guards to supervise forced labor or carry out administrative tasks in the camp. Also called "prisoner self-administration", the prisoner functionary system minimized costs by allowing camps to function with fewer SS personnel. The system was also designed to turn victim against victim, as the prisoner functionaries were pitted against their fellow prisoners in order to maintain the favor of their SS guards. If they were derelict, they would be returned to the status of ordinary prisoners and be subject to other prisoner functionaries. Many prisoner functionaries were recruited from the ranks of violent criminal gangs rather than from the more numerous political, religious and racial prisoners; those were known for their brutality toward other prisoners. This brutality was tolerated by the SS and was an integral part of the camp system.

Resettlement to the East was a Nazi euphemism which was used to refer to the deportation of Jews and others such as Gypsies to extermination camps and other murder locations as part of the Final Solution. The Nazis used the euphemism as an attempt to fool their victims into thinking that they would be "resettled" somewhere else, usually in a labour camp, but not all of the victims believed the claim. The Germans also used the word "evacuation", implying preservation from danger and equally misleading to the victims. The Jews were granted a small luggage allowance, but the luggage was loaded separately and it was often left at the station so it could be disposed of later, after the trains left. German Jews and their luggage were collected openly and in full view of the public before their transportation to the local railway station. To keep the lie credible, receipts were given, and the luggage was carried separately and collected from the victims after their murder.

The Schutzmannschaft or Auxiliary Police was the collaborationist auxiliary police of native policemen serving in those areas of the Soviet Union and the Baltic states occupied by Nazi Germany during World War II. Heinrich Himmler, head of the SS, established the Schutzmannschaft on 25 July 1941, and subordinated it to the Order Police. By the end of 1941, some 45,000 men served in Schutzmannschaft units, about half of them in the battalions. During 1942, Schutzmannschaften expanded to an estimated 300,000 men, with battalions accounting for about a third, or less than one half of the local force. Everywhere, local police far outnumbered the equivalent German personnel several times; in most places, the ratio of Germans to natives was about 1-to-10.

Sonderaktion 1005, also called Aktion 1005, or Enterdungsaktion, began in May 1942 during World War II to hide any evidence that people had been murdered by Nazi Germany in German-occupied Poland and Soviet Union. The project, which was conducted in secrecy from 1942 to 1944, focused on concealing evidence of mass murder at the Operation Reinhard killing centres, as well as at other sites. Groups of Sonderkommando prisoners, officially called Leichenkommandos, were used to exhume mass graves and burn the bodies; inmates were often put in chains to prevent them from escaping.

The SS Main Economic and Administrative Office was a Nazi organization responsible for managing the finances, supply systems and business projects of the Allgemeine-SS. It also ran the concentration camps and was instrumental in the implementation of the Final Solution through such subsidiary offices as the Concentration Camps Inspectorate and SS camp guards.

The SS Race and Settlement Main Office was the organization responsible for "safeguarding the racial 'purity' of the SS" within Nazi Germany.
Umschlagplatz was the term used during The Holocaust to denote the holding areas adjacent to railway stations in occupied Poland where Jews from ghettos were assembled for deportation to Nazi death camps. The largest collection point was in Warsaw next to the Warsaw Ghetto. In 1942 between 254,000 – 265,000 Jews passed through the Warsaw Umschlagplatz on their way to the Treblinka extermination camp during Operation Reinhard, the deadliest phase of the Holocaust in Poland. Often those awaiting the arrival of Holocaust trains, were held at the Umschlagplatz overnight. Other examples of Umschlagplatz include the one at Radogoszcz station - adjacent to the Łódź Ghetto - where people were sent to Chełmno extermination camp and Auschwitz.

Untermensch is a Nazi term for non-Aryan "inferior people" often referred to as "the masses from the East", that is Jews, Roma, and Slavs. The term was also applied to Mulatto and Black people. Jewish, Polish and Romani people, along with the physically and mentally disabled, were to be exterminated in the Holocaust. According to the Generalplan Ost, the Slavic population of East-Central Europe was to be reduced in part through mass murder in the Holocaust, with a majority expelled to Asia and used as slave labor in the Reich. These concepts were an important part of the Nazi racial policy.

Nazi Germany used six extermination camps, also called death camps (Todeslager), or killing centers (Tötungszentren), in Central Europe during World War II to systematically murder over 2.7 million people – mostly Jews – in the Holocaust. The victims of death camps were primarily killed by gassing, either in permanent installations constructed for this specific purpose, or by means of gas vans. The six extermination camps were Chelmno, Belzec, Sobibor, Treblinka, Majdanek and Auschwitz-Birkenau. Auschwitz and Majdanek death camps also used extermination through labour in order to kill their prisoners.