Digital currency or
digital money is an Internet-based
medium of exchange distinct from physical (such as
banknotes and
coins) that exhibits properties similar to physical currencies, but allows for instantaneous transactions and borderless transfer-of-ownership. Both
virtual currencies and
cryptocurrencies are types of digital currencies, but the converse is incorrect. Like traditional
money these currencies may be used to buy physical
goods and services but could also be restricted to certain communities such as for example for use inside an on-line game or social network. Digital currencies such as
bitcoin are known as "
decentralized digital currencies," meaning that there is no central point of control over the money supply.