What was the Cold War and why did it happen?

The Cold War was a period of geopolitical tension between the United States and the Soviet Union, and their respective allies, following World War II. It was characterized by political and military rivalry, nuclear arms race, and ideological conflict. It happened due to the contrasting ideologies of capitalism and communism, competition for global influence, and fear of mutual destruction through nuclear warfare. The Cold War shaped the global political landscape and had a profound impact on international relations, leading to proxy wars and the division of the world into two opposing blocs.