The term Eastern world refers very broadly to the various cultures or social structures and philosophical systems, depending on the context, most often including at least part of Asia or geographically the countries and cultures east of Europe, north of Oceania. The term is usually not used by non-Europeans since this Eastern world is a varied, complex and dynamic region, hard to generalize, and although these countries and regions have many common threads running through them, historically they never needed to define themselves collectively against another entity, real or superficial.