The Auschwitz concentration camp complex was a system of concentration camps (German: Konzentrationslager, abbreviated as either KL or KZ) run by Nazi Germany in occupied Poland from 1940 to 1945. The main camp (German: Stammlager) was Auschwitz I. Auschwitz II, or Birkenau, was a concentration and extermination camp, and became the most notorious of the camps. Auschwitz III, or Monowitz, was a labour camp.
In addition to the three largest camps, Auschwitz consisted of several subcamps. The satellite camps were named Aussenlager (external camp), Nebenlager (extension or subcamp), and Arbeitslager (labour camp). Several lay within 10Â km (6.2Â mi) of the main camp, with prisoner populations ranging from dozens to several thousand.