Electronic cash has the characteristics of real money, like anonymity, off-line nature, can not be tracked and so on. In order to simulate real money better, it can be also divisible and unlinkable. 电子现金具有现实货币的特性,具有匿名性,离线性,不可追踪性等特点,为了更好的模拟现实货币,还具有可分性、不可连接性等特点。