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,
World currency desire for a new supranational reserve currency by showing off a coin minted with the words "unity in diversity". The coin, an example of a future world currency, emphasized his call for creating a mix of regional currencies as a way to address the global financial crisis. On 30 March 2009, at the Second South America-Arab League Summit in Qatar, Venezuelan President Hugo Chavez proposed the creation of a petro-currency. It would be backed by the huge oil reserves of the oil producing countries. An alternative definition of a world or global currency refers to a hypothetical single global currency