A blockchain is a distributed, append-only ledger of records (blocks) chained together cryptographically. Each block contains a cryptographic hash of the previous block, ensuring immutability. Bitcoin introduced the first practical implementation in 2008, solving the double-spend problem without a central authority.
2008
Satoshi Nakamoto publishes the Bitcoin whitepaper
2009
First blockchain — Bitcoin — goes live
2015
Ethereum introduces programmable blockchain
2017
Enterprise blockchain boom — IBM, Microsoft, and banks launch projects
2023
Most enterprise blockchain projects quietly abandoned
Trustless record-keeping, cryptocurrency, supply chain, voting, digital identity
💡 Did You Know
The word blockchain does not appear in Satoshi Nakamoto's original Bitcoin whitepaper — the concept was described but not named
⚠ Controversies & Red Flags
Enterprise blockchain projects — often just distributed databases with limited decentralisation — have been widely criticised as solutions looking for problems.