Origins of digital currencies date back to the 1990s Dot-com bubble . One of the first was E-gold , founded in 1996 and backed by gold. Another known digital currency service was Liberty Reserve , founded in 2006; it let users convert dollars or euros to Liberty Reserve Dollars or Euros, and exchange them freely with one another at a 1% fee. Both services were centralized, reputed to be used for money laundering, and inevitably shut down by the US government. [3] Q coins or QQ coins, were used as a type of commodity-based digital currency on Tencent QQ 's messaging platform and emerged in early 2005. Q coins were so effective in China that they were said to have had a destabilizing effect on the Chinese Yuan or RMB currency due to speculation. [4] Recent interest in cryptocurrencies has prompted renewed interest in digital currencies, with bitcoin , introduced in 2009, becoming the most widely used and accepted digital currency. Types of digital currencies