Double-spend problem
Programming[1]
Double-spending is a problem in which the same digital currency can be spent more than once. ... It is not ideal for the same digital currency to be spendable more than once, because it can result in a loss of trust in that currency, making it effectively worthless.[2]
Double-spending is a potential flaw in a digital cash scheme in which the same single digital token can be spent more than once. Unlike physical cash, a digital token consists of a digital file that can be duplicated or falsified. [3]
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