The European Union (EU) is a political and economic union of 27 member states located primarily in Europe. The EU was established by the Treaty of Maastricht in 1993 and it is based on the principles of freedom, democracy, equality, and the rule of law. The EU aims to promote economic and social progress, protect human rights and fundamental freedoms, and strengthen the common European identity. The EU has a common market with free movement of goods, services, capital, and people among its member states. It also has a single currency, the euro, which is used by 19 of its member states. The EU has its own institutions, including the European Commission, the European Parliament, the Council of the European Union, the European Council, and the Court of Justice of the European Union.