What is blockchain and how does it work?
A blockchain is a digital record of transactions. The name comes from its structure, in which individual records, called blocks, are linked together in a single list, called a chain. Blockchains are used for recording digital transactions. Each transaction added to the blockchain is validated by multiple peers in a peer-to-peer network. They work together to ensure each transaction is valid before it’s added to the blockchain. This decentralized network ensures a single system cannot add invalid transactions or blocks to the chain.
When a new block is added to a blockchain, it’s linked to the previous block using a cryptographic hash generated from the contents of the previous block. This ensures the chain never breaks and that each block is permanently recorded. It is also almost impossible to alter past transactions in blockchain since all the subsequent blocks must be altered first.