Many rely on blockchain, a technology that allows a decentralized crypto bank to review and approve transactions. The blockchain is similar to a digital register: all actors in a network receive a copy of this register and can reject any attempt to modify it. The blockchain actually acts as a database, allowing large volumes of information to be stored that cannot be changed. However, by relying on a peer-to-peer network to verify any new transaction added to the blockchain, the approach to trusting cryptocurrencies differs from that of traditional currencies.