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Security · Modern Bitcoin

51% attacks

A miner or coalition with majority hashpower can potentially reorganize recent blocks or censor transactions, but cannot arbitrarily create bitcoin or spend coins without valid signatures.

Why it matters

A miner or coalition with majority hashpower can potentially reorganize recent blocks or censor transactions, but cannot arbitrarily create bitcoin or spend coins without valid signatures.

Key ideas

Primary and technical sources

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

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