what are the functions of the united nations?
To maintain international peace and security, develop friendly relations among nations, achieve international cooperation, and be a centre for harmonizing the actions of nations
United Nations
The United Nations (UN) is an intergovernmental organization that aims to maintain international peace and security, develop friendly relations among nations, achieve international cooperation, and be a centre for harmonizing the actions of nations
give the detailed information about the uno before its foundation The UN was formulated and negotiated among the delegations from the Allied Big Four  at the Dumbarton Oaks Conference from 21 September 1944 to 7 October 1944 and they agreed on the aims, structure and functioning of the UN.
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United Nations [SEP] Introduction
The United Nations (UN) is an intergovernmental organization that aims to maintain international peace and security, develop friendly relations among nations, achieve international cooperation, and be a centre for harmonizing the actions of nations. It is the largest, most familiar, most internationally represented and most powerful intergovernmental organization in the world. The UN is headquartered on international territory in New York City, with its other main offices in Geneva, Nairobi, Vienna and The Hague. The UN was established after World War II with the aim of preventing future wars, succeeding the ineffective League of Nations. On 25 April 1945, 50 governments met in San Francisco for a conference and started drafting the UN Charter, which was adopted on 25 June 1945 and took effect on 24 October 1945, when the UN began operations.