The European Union (EU) is a political and economic union of 27 European countries created by the Maastricht Treaty in 1993 to promote economic integration, political cooperation, and peace in Europe. It operates a single market that allows the free movement of goods, services, capital, and people between member states, and 20 countries use the common currency, the Euro. The EU has shared institutions including the European Commission, European Parliament, and Council of the European Union, which coordinate legislation and policy across member states. Countries may leave the EU through a formal withdrawal process under Article 50 of the EU treaties, as demonstrated when the **United Kingdom exited the EU following the Brexit process completed in 2020.