Blockchain is a type of digital ledger technology that is used to securely and safely store records of transactions. It works by grouping transactions into blocks, which are then added in a chronological chain (hence the name) and encrypted using cryptography. This means that blockchain records are tamper-proof and viewable only by the parties involved in the transaction.
Blockchain is closely related to cryptocurrency because it is used to record and verify transactions. When a user sends or receives cryptocurrency, this transaction is recorded on the blockchain, allowing the funds to be securely sent and received without any third party interference. Blockchain also helps to ensure the security of the cryptocurrency network by confirming the legitimacy of all transactions.