The mass extermination of millions of Jews, homos, gypsies, and anyone who opposed Hitler. He made his ass- nazis shoot them right out and put them in mass grave, or put them in concentration camps. These were made especialy to kill and sicken the inhabitants. Some of the soldiers were good however, and were only there becuase they served int he army. It was becuase of good ppl like that that the few that survived did.
The holocaust was a terrible catastrophe that can't happen again. In order for it to not happen, EVERYONE needs to know abt it.