What Is a Blockchain and How Does It Work? Definition & Applications

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Blockchains are public-facing and unalterable, so they are a way to facilitate and store digital transactions. 

What Is a Blockchain in Simple Terms?

A blockchain, at its most basic level, is a digital ledger of transactions stored on many different computers (called nodes) that are linked by a network. It is composed of a series of “blocks,” which are essentially digital baskets that can be filled with records of transactions. Once the transactions in a block are verified via a consensus between nodes in the network, that block is “closed” and added to the existing, unalterable, chronological chain of previous blocks.