Blockchain – A blockchain is a decentralized ledger of transactions across a peer-to-peer network. Each transaction is recorded in an immutable and date/timestamped way and cannot be overwritten. All new transactions to the entity, such as a cryptocurrency, that the blockchain is associated with cause a new block to be appended to the chain. Each node in the peer-to-peer network has access to the blockchain, thus ensuring that the transaction history is open and transparent.