The document defines key terms and events of the Cold War between the United States and Soviet Union from 1947-1991. It discusses the tensions that arose after World War 2 over differing economic ideologies of capitalism versus communism. Major events that demonstrated the conflict included the Truman Doctrine providing aid to countries threatened by communism, the Marshall Plan rebuilding Europe, the Berlin Blockade and Crisis, the formation of NATO, and both nations developing atomic weapons.