Isobars are atoms that have same atomic mass but different atomic number. They have different atomic numbers because they have different numbers of protons. They have the same atomic mass because they have just enough neutrons to make the same total of nucleons. Isobars occur at different places in the Periodic Table.
The Holocaust (also called Ha-Shoah in Hebrew) refers to the period from January 30, 1933 - when Adolf Hitler became chancellor of Germany - to May 8, 1945, when the war in Europe officially ended.
What was it? The Holocaust is one of the most terrible events in human history. It occurred during World War II when Hitler was leader of Germany. Six million Jewish people were murdered by the Nazis. This included as many as 1 million Jewish children. Millions of other people that Hitler didn't like were killed as well. This included Polish people, Catholics, Serbs, and handicapped people.