Blockchain is a digital database containing information such as records of financial transactions that can be simultaneously used and shared within a large decentralized, publicly accessible network. Decentralized blockchains remain permanent, which means that all the information entered is irreversible, for cryptocurrency it implies that all transactions and financial processes are recorded and accessible for everyone.
Many cryptocurrencies are decentralized networks based on blockchain technology—a distributed ledger enforced by a disparate network of computers.