The United Nations (UN) works on a variety of issues to maintain international peace and security, promote human rights, and support sustainable development: 

Peace and security: The UN works to prevent conflict, help parties in conflict make peace, and create conditions for peace to flourish. The UN Security Council has primary responsibility for international peace and security. 

Human rights: The UN promotes human rights and fundamental freedoms for all, without distinction based on race, sex, language, or religion. 

Humanitarian aid: The UN provides humanitarian assistance. 

Sustainable development: The UN supports sustainable development and climate action, including the 2030 Agenda for Sustainable Development. 

International law: The UN upholds international law. 

Other issues: The UN also works on: 

Protecting the environment 

Supporting refugees 

Disaster relief 

Countering terrorism 

Disarmament and non-proliferation 

Promoting democracy 

Gender equality 

Governance 

Economic and social development 

International health 

The UN was established in 1945 after World War II. Its six principal organs are:

General Assembly

Security Council

Economic and Social Council

Trusteeship Council

International Court of Justice

Secretariat