Bitcoin for the Technically Curious

As described on the blockchain page, Haber and Stornetta devised a system using a cryptographically secured chain of blocks and it was the original solution. This initial concept, however, still relied on a central authority to manage the chain. The true innovation came in 2008 when the pseudonymous Satoshi Nakamoto introduced the first decentralized blockchain as the public ledger for Bitcoin.

Nakamoto's key addition was to make the ledger distributed across a peer-to-peer network, meaning there was no single central authority. This solved a major problem of digital currency: double-spending. By using a decentralized, timestamped, and cryptographically secure chain, the network could verify that a transaction was a true, one-time event without needing a bank or other intermediary.

In essence, blockchain evolved from a simple timestamping tool into a powerful technology for creating a trustless, decentralized system for recording any kind of transaction, not just documents.