Customary international law：

Recognition of customary international law

The International Court of Justice Statute defines customary international law in Article 38(1)(b) as "evidence of a general practice accepted as law."^[1] This is generally determined through two factors: the general practice of states and what states have accepted as law.^[2]

There are several different kinds of customary international laws recognized by states. Some customary international laws rise to the level of jus cogens through acceptance by the international community as non-derogable rights, while other customary international law may simply be followed by a small group of states. States are typically bound by customary international law regardless of whether the states have codified these laws domestically or through treaties.

短短的8行字而已。