The Holocaust refers to the systematic persecution and murder of approximately 6 million Jews by the Nazi regime and its allies between 1933 and 1945. In addition to Jews, the Nazi regime also targeted millions of others they deemed "undesirable" or "subhuman" including Russians, Poles, Roma people, disabled individuals, and others. Over 1 million children were killed during the Holocaust. Most victims were killed in concentration camps like Auschwitz, where between 1-2.5 million people were murdered and the average weight of women was only 22-29 kilograms.