European integration refers to the process of unifying European countries to promote economic, political, and social cooperation. This effort began after World War II to prevent future conflicts and has led to the establishment of institutions like the European Union (EU), which facilitates trade and movement among member states. The integration process includes various treaties and agreements, such as the Treaty of Rome and the Maastricht Treaty, which have expanded cooperation in areas like the economy, security, and environmental policy. Today, the EU consists of 27 member countries, working together to address common challenges and enhance stability in the region.