Electronic money systems

In technical terms, electronic money is an online representation, or a system of debits and credits, used to exchange value within another system, or within itself as a stand alone system. In principle this process could also be done offline.
Occasionally, the term electronic money is also used to refer to the provider itself. A private currency may use gold to provide extra security, such as digital gold currency. Some private organizations, such as the United States armed forces use independent currencies such as Eagle Cash.

Centralised systems

Many systems—such as PayPal, WebMoney, Payoneer, cashU, and Hub Culture's Ven—will sell their electronic currency directly to the end user, but other systems only sell through third party digital currency exchangers.
In the case of Octopus card in Hong Kong, electronic money deposits work similarly to regular bank deposits. After Octopus Card Limited receives money for deposit from users, the money is deposited into a bank. This is similar to debit-card-issuing banks redepositing money at central banks.
In Kenya, the M-Pesa system is being used to transfer money through mobile phones.^[2]
Some community currencies, like some local exchange trading systems (LETS) and the Community Exchange System, work with electronic transactions.

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