International relations (IR, and also referred to as international studies, international politics, or international affairs) is an academic discipline. In a broader sense, the study of IR, in addition to multilateral relations, concerns all activities among states—such as war, diplomacy, trade, and foreign policy—as well as relations with and among other international actors, such as intergovernmental organizations (IGOs), international nongovernmental organizations (INGOs), international legal bodies, and multinational corporations (MNCs). International relations is generally classified as a major multidiscipline of political science, along with comparative politics, political methodology, political theory, and public administration. It often draws heavily from other fields, including anthropology, economics, geography, history, law, philosophy, and sociology. There are several schools of thought within IR, of which the most prominent are realism, liberalism, and constructivism. While international politics has been analyzed since antiquity, it did not become a discrete field until 1919, when it was first offered as an undergraduate major by Aberystwyth University in the United Kingdom. The Second World War and its aftermath provoked greater interest and scholarship in international relations, particularly in North America and Western Europe, where it was shaped considerably by the geostrategic concerns of the Cold War. The collapse of the Soviet Union and subsequent rise of globalization in the late 20th century have presaged new theories and evaluations of the rapidly changing international system. Source: Wikipedia (en)