Blockchain technology as we know it today originated from the 2008 Bitcoin whitepaper ↗ by Satoshi Nakamoto, an alias. Although Nakamoto never referred blockchain specifically in the context of Bitcoin, calling it as a “chain of hash-based proof-of-work,” and a “chain of blocks” instead, the pseudonymous creator was the first to implement it in practice. Blockchain – also called distributed ledger technology (DLT) - is a shared, immutable ledger that facilitates the recording of transactions in a network without relying on a trusted central authority.
At the most basic level, the blockchain is nothing but list of records - called blocks - that are linked using cryptography. It is a simple data structure that grows over time as more blocks are appended. This data structure, with its inclusion of cryptographic hashes of previous blocks, ensures that potential alterations to past records can be easily detected and the database is consistent. Providing the database to every node in a peer-to-peer network ensures that it can’t be shut down or changed unilaterally.
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