The Cold War was a period of geopolitical tension between the United States and the Soviet Union that lasted from the end of World War II in 1947 until the early 1990s. It was characterized by a struggle for global influence, marked by ideological differences between capitalism and communism. During this time, both superpowers engaged in an arms race, developing nuclear weapons and military alliances like NATO and the Warsaw Pact. The conflict also included proxy wars, espionage, and competition in technology and space exploration, notably the Space Race, which included events like the launch of Sputnik.