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Khan Academy
Khan Academy: Bitcoin: Bitcoin the Security of Transaction Block Chains
A detailed explanation of what makes bitcoin transaction block chains secure. [15:16]
Khan Academy
Khan Academy: Bitcoin: Bitcoin: Transaction Block Chains
The mechanics of a bitcoin transaction block chain, which is a construct that is generated by bitcoin miners and functions as a global ledger for recording and validating bitcoins. [11:25]
Khan Academy
Khan Academy: Bitcoin: Proof of Work
An explanation of cryptographic proof-of-work protocols, which are used in various cryptographic applications and in bitcoin mining. [10:31]