World War Two was an international conflict from 1939-1945 involving many world powers split into two opposing military alliances - Allies and Axis Powers. It was marked by significant events such as Holocaust, atomic bombings on Japan, etc., and ended with Allied victory.
Related terms
Holocaust: The systematic genocide carried out by Nazi Germany leading to approximately six million Jewish deaths during World War II.
Pearl Harbor Attack: A surprise military strike by Japanese against United States naval base at Pearl Harbor in Hawaii on December 7, 1941 which led to the U.S. entering World War II.
D-Day: The day (June 6, 1944) in World War II on which Allied forces invaded northern France by means of beach landings in Normandy.