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Double spending

A double spend is an attempt to spend the same bitcoin output more than once. Bitcoin’s validation rules and proof-of-work ordering resolve conflicting spends.

Why it matters

A double spend is an attempt to spend the same bitcoin output more than once. Bitcoin’s validation rules and proof-of-work ordering resolve conflicting spends.

Key ideas

Primary and technical sources

Bitcoin Developer DocumentationBitcoin.orgBitcoin: A Peer-to-Peer Electronic Cash SystemSatoshi Nakamoto

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