The Polar Crown is the regional currency of Antarctica. Having a single regional currency allows greater economic freedom, but it does sometimes erode national identity. For this reason, conversion to the Polar Crown has always been optional. In order to assure some of the benefits of a regional currency, while allowing nations to maintain their national identity, adding the prefix Polar to any national currency is the equivalent of converting to the Polar Crown. A large number of nations in the region use the Polar Crown and there are also many who use the Polar prefix in front of their national currencies.