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,
Digital gold currency security token that changes the passphrase with each logon, but charges the account holder USD $99.50 for the token. E-bullion does not require customers to use the Cryptocard, so account holders who choose not to get one may suffer from the same security issues as e-gold customers. Pecunix devised a unique rotating key system that provides many of the benefits of a security token without requiring the user to buy one. Pecunix also supports the use of PGP signatures to access an account, which is probably the strongest of all authentication methods. Digital gold currency is a form of representative