Sources of international law include treaties, international customs, general principles of law as recognised around the world, the decisions of national and lower courts, and scholarly writings. They are the materials and processes out of which the rules and principles regulating the international community are developed. They have been influenced by a range of political and legal theories.

States and non-state actors like individuals, international organisations, multinational companies and international non-governmental organisations are regulated by, or subjected to, international law. They are called subjects of international law. These subjects have international legal personality. In other words, they have certain rights and duties under international law and they can exercise these rights and duties.

Opinio juris sive necessitatis (an opinion of law or necessity) or simply opinio juris (an opinion of law) is the belief that an action was carried out because it was a legal obligation.

The United Nations was established by the Charter of the United Nations and statute of the international court of justice. The Charter was signed on June 26, 1945 by the representatives of 50 countries; Poland signed on October 15, 1945. In 1945, 51 members founded it.

Sources of international law include treaties, international customs, general principles of law as recognised around the world, the decisions of national and lower courts, and scholarly writings. Constitution is not a source of international law.

In the resolution incorporating the outcome of the World Summit in September 2005, the UN General Assembly affirmed that the relevant provisions of the UN Charter are sufficient to address the full range of threats to international peace and security, and has reaffirmed the authority of the Security Council to mandate coercive action to maintain and restore peace and security. But the resolution did not deal with the question as to when it is lawful for a state to use force in the exercise of its inherent right of self-defence.

International law or the Law of Nations is the name of a body of rules which, according to their usual definitions, regulate the conduct of states in their intercourse with each other.

The judgment shall be signed by the President and the Registrar. It shall be read in open court. Due notice shall be given to the agents.

The ICJ considered the WHO's request, in a case known as the Legality of the Use by a State of Nuclear Weapons in Armed Conflict, and also known as the WHO Nuclear Weapons Case, between 1993 and 1996. After considering the case, the Court refused to give an advisory opinion on the WHO's question.

The official languages of the Court are French and English. If the parties agree that the case shall be conducted in French, the judgment shall be delivered in French. If the parties agree that the case shall be conducted in English, the judgment shall be delivered in English.

The members of the Court shall be elected by the General Assembly and by the Security Council from a list of persons nominated by the national groups in the Permanent Court of Arbitration.

The UN Charter does not make any distinction between the original and subsequent members.

According to the Charter, the UN has four purposes:

1. To maintain international peace and security
2. To develop friendly relations among nations
3. To cooperate in solving international problems and promoting respect for human rights
4. To be a centre for harmonising the actions of nations

The United Nations is not a world government and it does not make laws. It does, however, provide the means to help resolve international conflicts and formulate policies on matters affecting all of us. At the UN, all the member states, large and small, rich and poor, with differing political views and social systems, have a voice and a vote in this process.

The Secretariat is the United Nations' executive arm. The Secretariat has an important role in setting the agenda for the UN's deliberative and decision making bodies of the UN (the General Assembly, Economic and Social Council, and Security Council), and the implementation of the decisions of these bodies.

The General Assembly shall consider and approve the budget of the organisation. It is given under Article 17 of the Charter.