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,
Private currency permit the transfer of points or miles. Some startups, such as the Canadian website Points.com, have sought to make loyalty "points" more currency-like by creating an exchange where points from one loyalty program can be traded for points in other such programs. A cryptocurrency is a form of digital or virtual currency where cryptography secures the transactions and controls the creation of additional units of the currency. A cryptocurrency wallet can be used to store the public and private keys which can be used to receive or spend the cryptocurrency. The cryptographic systems used allow for decentralisation; a decentralised cryptocurrency