The standard unit of currency in Europe is the euro (€). The euro was introduced in 1999 as an electronic currency and began circulating as physical cash in 2002. It is used by 19 of the 27 European Union (EU) member states, collectively known as the Eurozone. The euro is one of the most significant currencies in the world, facilitating trade and economic stability among member countries. Its adoption aimed to enhance economic cohesion, simplify transactions, and promote a single market across Europe, fostering stronger economic ties among participating nations.