Digital currency bitcoin is a digital currency but also a type of virtual currency. Bitcoin and its alternatives are based on cryptographic algorithms, so these kinds of virtual currencies are also called cryptocurrencies. Most of the traditional money supply is bank money held on computers. This is also considered digital currency. One could argue that our increasingly cashless society means that all currencies are becoming digital, but they are not presented to us as such. Currency can be exchanged electronically using debit cards and credit cards using electronic funds transfer at point of sale. A number of electronic money systems use contactless
Reserve currency before the beginning of the worldwide credit crunch related recession and Eurozone crisis, which harmed the euro and slowed its adoption. Since 2009, the reserve currency use of the euro has continued to drop, down to 23.9 percent in 2013. The Dutch guilder was the "de facto" reserve currency in Europe in 17th and 18th centuries. The United Kingdom's pound sterling was the primary reserve currency of much of the world in the 19th century and first half of the 20th century. The emergence of the USA as an economic superpower, and the establishment of the U.S. Federal Reserve System