The United Nations is an international and intergovernmental organization which aims to foster cooperation within countries and to preserve international order. It was created in 1945, in the aftermath of WWII, with the principal objective of preventing another such conflict. It started gathering 51 member states, and nowadays it counts with 193 members.
Its headquarters are located in Manhattan in NY, and other main offices are located in Geneva, Vienna and Nairobi. Morover the UN is composed by 6 main institutions: General Assembly, Security Council, Economic and Social Council (ECOSOC), the Secretariat, the International Court of Justice and the UN Trusteeship Council .