Blockchain is a shared, immutable ledger that facilitates the process of recording transactions and tracking assets in a business network. Virtually anything of value can be tracked and traded on a blockchain network, reducing the risk and cutting costs for all involved. Unlike a typical digital database, blockchain stores data in blocks that are then chained together. As new data comes in, it is entered in a fresh block. Once the block is filled with data, it is chained to the previous block, which then chains the data in a chronological order. Blockchain’s most common use so far has been as a ledger for transactions. In the case of cryptocurrencies, blockchain is used in a decentralised way so that no single person or group has control over it and, instead, all users can retain control collectively. Decentralised blockchains are immutable, which means data once entered is irreversible. In the case of cryptocurrencies, this means transactions are recorded permanently and can be viewed by anyone.