A more thorough explanation:

International law refers to the set of rules and principles that govern the relationships and interactions between nations, as well as between states and individuals, and international organizations. It covers issues related to rights, obligations, and responsibilities of nations and individuals in the international community.

International law includes various fields such as:

• International economic law
• International security law
• International criminal law
• International environmental law
• Diplomatic law
• International humanitarian law, also known as the law of war
• International human rights law

These fields cover different aspects of international relations, such as trade, security, crime, environment, diplomacy, war, and human rights.

The primary sources of international law are customary law and conventional law. Customary international law is based on the consistent practices of states out of a sense of legal obligation. Conventional international law is derived from international agreements, such as treaties, and is binding on the parties that have agreed to it.

International agreements create law for the parties involved, and customary law and laws made by international agreements have equal authority as international law. General principles that are common to national legal systems can also be a secondary source of international law.

Traditionally, individual countries were the main subjects of international law. However, individuals and non-state international organizations have also become subject to international regulation. The United States typically respects the laws of other nations, unless there is some statute or treaty to the contrary. International law is typically a part of U.S. law only for the application of its principles on questions of international rights and duties.

International law can be illustrated by the United Nations Convention on the Law of the Sea, which sets out the legal framework for the use of the world's oceans and their resources. This convention is an example of conventional international law, as it was agreed upon by the parties involved. It also illustrates the domain of international environmental law, as it deals with the protection and conservation of the marine environment.