Digital currency founded DigiCash, an electronic cash company, in Amsterdam to commercialize the ideas in his research. It filed for bankruptcy in 1998. In 1999, Chaum left the company. In 1997, Coca-Cola offered buying from vending machines using mobile payments. After that PayPal emerged in 1998. Other systems followed suit, such as e-gold, but it faced issues because it was used by criminals and was closed by U.S Department of Justice in 2005. In 2008, bitcoin was introduced, which marked the start of digital currencies. Origins of digital currencies date back to the 1990s Dot-com bubble. One of the first was E-gold,
Virtual currency and (2) that persons may obtain by their own computing or manufacturing effort". Rather than relying on confidence in a central authority, it depends instead on a distributed system of trust. Digital currency is a particular form of currency that is electronically transferred and stored, i.e., distinct from physical currency, such as coins or banknotes. According to the European Central Bank, virtual currencies are "generally digital", although their enduring precursor, the coupon, for example, is physical. A cryptocurrency is a digital currency using cryptography to secure transactions and to control the creation of new currency units. Since not all virtual