For the 20th century brand, see ecash. It exhibits properties similar to physical currencies, redeem private key bitcoin mining allows for instantaneous transactions and borderless transfer-of-ownership. Digital currency is a money balance recorded electronically on a stored-value card or other device.
Another form of electronic money is network money, allowing the transfer of value on computer networks, particularly the Internet. Digital money can either be centralized, where there is a central point of control over the money supply, or decentralized, where the control over the money supply can come from various sources. In 1983, a research paper by David Chaum introduced the idea of digital cash. It filed for bankruptcy in 1998. In 1997, Coca-Cola offered buying from vending machines using mobile payments.