The European Union (EU) is a political and economic union of 27 European countries, established to foster economic cooperation, political stability, and social integration. The EU covers an area of approximately 4.5 million square kilometers and has a population of around 450 million people. It was founded to promote peace and prosperity in Europe after World War II, starting with the European Coal and Steel Community in 1951 and evolving into the EU with the Maastricht Treaty in 1993. The EU has its own currency, the euro, used by 19 of the member states. It focuses on areas like trade, environmental policy, human rights, and security. Brussels, Belgium, serves as the administrative capital, where major EU institutions are based. The EU is one of the largest economies in the world and plays a key role in international diplomacy.