Europe is the world's second-smallest continent in terms of area, although its population of about 710 million is the third largest - after Asia and Africa. Of Europe's 48 countries, Russia is its largest by area and population, while the Vatican City is the smallest.
In 2008, 27 of Europe's 48 countries, including the UK, now belong to the European Union (EU), which started in 1957 when 6 European countries formed the European Economic Community (EEC). The UK joined in 1973 at the same time as Ireland and Denmark.
In 1999 it introduced a common currency, the Euro, which has been adopted by 13 member states. It has also developed a role in foreign policy, justice and home affairs.
Find out more about what the EU does.
Negotiations to join the EU are also under way with a number of other candidate states, including Turkey, Croatia, and the former Yugoslav Republic of Macedonia.
Before being allowed to join the EU, a state must fulfil certain economic and political conditions. These basically require that a candidate country must enjoy a secular, democratic system of government, together with the corresponding freedoms and institutions, and respect for the rule of law.
Enlargement of the EU is conditional upon the agreement of each existing member state, as well as approval by the European Parliament.
There are a number of EU institutions - including the European Commission, European Parliament and the European Court of Justice - which are designed to ensure that:
You might also like to visit the Commission's YouTube channel for more information.
A number of European countries are not EU members but belong to other groupings. The member states of the European Free Trade Association (EFTA) are allowed to participate in the European Economic Area without joining the EU.
Other Western European countries, including Andorra, Monaco, San Marino and the Vactican City aren't members of the EU or EFTA.