In geography, regions are areas broadly divided by physical characteristics (physical geography), human impact characteristics (human geography), and the interaction of humanity and the environment (environmental geography). Geographic regions and sub-regions are mostly described by their imprecisely defined, and sometimes transitory boundaries, except in human geography, where jurisdiction areas such as national borders are clearly defined in law.

Régional Compagnie Aérienne Européenne, or Régional for short, is a subsidiary airline wholly owned by Air France which connects hubs at Paris, Lyon to 49 airports in Europe. The airline operated in Air France livery, retaining its name in small titles and logo on the front fuselage and engines. It became the first European operator of the Embraer 190 aircraft in November 2006. It was headquartered in Bouguenais at the Nantes Atlantique Airport.