The term "Holocaust," originally from the Greek word "holokauston" which means "sacrifice by fire," refers to the Nazi's persecution and planned slaughter of the Jewish people. The Hebrew word "Shoah," which means "devastation, ruin, or waste," is also used for this genocide.
In addition to Jews, the Nazis targeted Gypsies, homosexuals, Jehovah's Witnesses, and the disabled for persecution. Anyone who resisted the Nazis was sent to forced labor or murdered.