The United Nations, commonly known as the UN, is an intergovernmental organization founded in 1945 after the end of World War II. Its headquarters is located in New York City, USA, and its membership currently consists of 193 member states. The UN's primary purpose is to promote international cooperation and maintain peace and security among nations. It does this through a variety of means, including peacekeeping operations, mediation and conflict resolution, and humanitarian aid. The UN also focuses on a range of other issues, including human rights, climate change, and gender equality. It has established a number of specialized agencies, such as the World Health Organization and the United Nations Children's Fund, to address these issues. Overall, the UN plays a crucial role in promoting global cooperation and addressing some of the world's most pressing challenges.