International law, also known as public international law and law of nations, is the set of rules, norms, and standards generally accepted in relations between nations. It establishes normative guidelines and a common conceptual framework to guide states across a broad range of domains, including war, diplomacy, trade, and human rights. International law thus provides a means for states to practice more stable, consistent, and organized international relations.
The sources of international law include international custom (general state practice accepted as law), treaties, and general principles of law recognized by most national legal systems. International law may also be reflected in international comity, the practices and customs adopted by states to maintain good relations and mutual recognition, such as saluting the flag of a foreign ship or enforcing a foreign judgment.
Diplomacy is the art and practice of conducting negotiations between representatives of states. It usually refers to the conduct of international relations through the intercession of professional diplomats with regard to a full range of topical issues. Diplomacy entails influencing the decisions and conduct of foreign governments and officials through dialogue, negotiation, and other nonviolent means.