Champagne is a sparkling wine produced by inducing the in-bottle secondary fermentation of wine to effect carbonation. It is produced exclusively within the Champagne region of France, from which it takes its name. While the term "champagne" is used by some makers of sparkling wine in other parts of the world, numerous countries limit the use of the term to only those wines that come from the Champagne appellation. In Europe, this principle is enshrined in the European Union by Protected Designation of Origin (PDO) status. Other countries, such as the United States, have recognized the exclusive nature of this name, yet maintain a legal structure that allows longtime domestic producers of sparkling wine to continue to use the term "Champagne" under specific circumstances.