The EC (the European Community) was renamed the EU (the European Union) when the Treaty on European Union (Maastricht Treaty) came into force on 1 November 1993.
The EU was established through the Maastricht Treaty. The basis for EU cooperation is formed by both the Treaty on European Union and the Euratom Treaty.
EU cooperation is used as a collective term for the work that is carried out within the frameworks of these treaties.