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Inventor of HashcashCypherpunk precursors✓ Verified
Adam Back
Created Hashcash — Bitcoin's proof-of-work.
Known as Adam BackActive Mar 1997 →
Why they matter
Bitcoin's mining mechanism is Hashcash applied to a chain of blocks. Back's cost-function idea — make an action cheap to verify but expensive to produce — is the engine of Nakamoto consensus.
Profile
British cryptographer who invented Hashcash in 1997, a proof-of-work system originally designed to limit email spam and denial-of-service attacks. Satoshi contacted him early; Hashcash is reference [6] in the white paper. He later co-founded Blockstream.