The United Nations is an international organization formed in 1945 to promote world peace and cooperation. It aims to maintain international peace and security, develop friendly relations among nations, achieve international cooperation, and be a center for harmonizing the actions of nations. The United Nations has six main organs that carry out its duties: the General Assembly, Security Council, Economic and Social Council, Trusteeship Council, International Court of Justice, and Secretariat. The Secretary-General leads the UN Secretariat and heads the entire UN system.