Blockchain is a method of recording information that makes it near-impossible to change or hack. Sometimes referred to as distributed ledger technology (DLT), a blockchain is essentially a digital ledger of transactions that is duplicated and distributed across an entire peer-to-peer network. Each transaction added to a blockchain is validated by multiple computers in the network, ensuring that a single system cannot add invalid blocks.
For additional security, when a new block is added to a blockchain, it is linked to the previous block using an immutable cryptographic signature called a hash. This ensures the chain is never broken and that each block is permanently recorded, since the only way to alter past transactions in blockchain is to alter all subsequent blocks first.
Blockchain technology is at the heart of cryptocurrencies like Bitcoin, and smart contracts (decentralized applications and transaction protocols) that enable Decentralized Finance (DeFi).
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