The United Nations (UN) is an intergovernmental organization that was tasked to maintain international peace and security, develop friendly relations among nations, achieve international co-operation and be a centre for harmonizing the actions of nations. The headquarters of the UN is in Manhattan, New York City, and is subject to extraterritoriality. Further main offices are situated in Geneva, Nairobi, and Vienna. The organization is financed by assessed and voluntary contributions from its member states. Its objectives include maintaining international peace and security, protecting human rights, delivering humanitarian aid, promoting sustainable development and upholding international law. The UN is the largest, most familiar, most internationally represented and most powerful intergovernmental organization in the world. In 24 October 1945, at the end of World War II, the organization was established with the aim of preventing future wars. At its founding, the UN had 51 member states; there are now 193. The UN is the successor of the ineffective League of Nations.