# 2.4 双重支付（双花）

双重支付又被称为“双花”，顾名思义就是同一笔钱（数字加密货币）被重复支付两次，也就是将同一个地址上的数字加密货币同时支付给两个不同的收款地址。

比特币双花一直都有，只是这些双花没成功而已。

如果双重支付是有意而为之，那么就是双花攻击。在其它公链上双花攻击的确多次发生过，并且不幸的是作恶者硕果累累。


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