Adolf Hitler said that the Jews were the reason that Germany lost World War 1, so he created a group called Nazis and used them to get rid of all the Jews. Life in the concentration camps were horrible for the Jews.
There were 3 types of concentration camps: imprisonment, slave labor, and death camps. At death camps there would be rooms for "showers" but the rooms would be filled up with chemical gas that would kill everybody in the room.
In slave labor camps the German soldiers would force the Jews to do hard labor, without any help.