A virtual currency or virtual money has been defined in 2012 by the European Central Bank as "a type of unregulated, digital money, which is issued and usually controlled by its developers, and used and accepted among the members of a specific virtual community". The US Department of Treasury in 2013 defined it more tersely as "a medium of exchange that operates like a currency in some environments, but does not have all the attributes of real currency". The key attribute a virtual currency does not have according to these definitions, is the status as legal tender. Virtual currency that substitutes legal tender has been known as a scrip.
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