The primary currency used in the Eurozone is the euro (€). The euro was introduced in 1999 as an electronic currency and became physical cash in 2002, replacing many national currencies across Europe. The Eurozone comprises 19 of the 27 European Union (EU) member states that have adopted the euro as their official currency. This common currency facilitates easier trade and investment among member countries, promoting economic stability and integration. The European Central Bank (ECB) oversees monetary policy and aims to maintain price stability within the Eurozone, reinforcing the euro's position as one of the world's leading currencies.