Imperial core, also known as the First World or Western world, is a term which refers to imperialist countries which have historically benefited from unequal exchange with periphery countries. As a result of the core-periphery relationship, imperial core countries pressure periphery countries economically, politically and sometimes militarily to be dependent of the imperial core countries. Some notable examples of countries in the imperial core include the USA and the United Kingdom, as both of these countries have benefited from imperialism.