What is a blockchain used for?

A blockchain is a decentralized, distributed, and oftentimes public, digital ledger consisting of records called blocks that are used to record transactions across many computers so that any involved block cannot be altered retroactively, without the alteration of all subsequent blocks .

: 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 also : the technology used to create such a database The technology at the heart of bitcoin and other virtual currencies, …

A blockchain is a digital, public ledger that records online transactions . Blockchain is the core technology for cryptocurrencies like bitcoin. A blockchain ensures the integrity of a cryptocurrency by encrypting, validating, and permanently recording transactions.