Adolf Hitler called it "The Final Solution" but the Allied Forces called it murder. They called it "The Holocaust".
Jews
They called it "Schutzhaft" - "protective custody". They were "protecting" the Jews (or whoever they were arresting if not Jews) from the wrath of the German people.
No. Not all Germans are Jews and not all Jews are German. But there are German Jews, as well as Jews with many other nationalities.
In Holocaust and related literature the long huts are (misleadingly) called barracks. This is a mistranslation of the German word Barracke, which means (prefabricated) hut.
If the question is: Why did they gas (rather than shoot/etc.) the Jews? The Answer is: shooting (the previous execution method) was causing psychological problems for the execution squads and was taking too much time. Gassing was simply more efficient. If the question is: Why did they kill Jews? The Answer is: Hitler build upon latent anti-Semitism in Germany to create an environment where Jews were blamed for prior German problems and defeats. Successful de-humanization campaigns during the 1930s resulted in Hitler being able to push a program of simple mass-execution of Jews, as a "service to mankind".
The Jews were the main target in Germany. The German genocide is also called the Holocaust.
People who were not Jews were treated differently than the Jews in Nazi Germany. Some of the Jews were German citizens but they were treated as Jews.
They had to hate jews even if they liked them (it was their job)
They had to hate jews even if they liked them (it was their job)
They had to hate jews even if they liked them (it was their job)
The plan to kill all Jews was called the Final Solution, in which means that the mass murdering of Jews, in 1942 after the Final solution was decided, 3 million jews were murdered in a single year, 8,000+ dying daily.