International law is the term commonly used for referring to the system of implicit and explicit agreements that bind together nation-states in adherence to recognized values and standards. It differs from other legal systems in that it primarily concerns states rather than private citizens. However, the term "international law" can refer to three distinct legal disciplines: The two traditional branches of the field are: Sources of international law are the materials and processes out of which the rules and principles regulating the international community developed.
They have been influenced by a range of political and legal theories. During the 20th century, it was recognised by legal positivists that a sovereign state could limit its authority to act by consenting to an agreement according to the principle pacta sunt servanda. This consensual view of international law was reflected in the 1920 Statute of the Permanent Court of International Justice, and preserved in Article of the 1946 Statute of the International Court of Justice.