The Nazis built six death camps — Belzec, Chelmno, Sobibor, Treblinka, Auschwitz-Birkenau, and Majdanek — for the specific purpose of murdering the Jews of Europe. The camps were designed to kill the prisoners and dispose of their bodies with machine-like efficiency. Victims at most camps were gassed with carbon monoxide; at Auschwitz-Birkenau, the Nazis used a poison gas called Zyklon B. Since ghettos and the Einsatzgruppen killing squads were inefficient and highly visible ways of killing Jews, the death camps were essential to carrying out the Final Solution.
