What is Proof-of-Work

Proof-of-Work is the basis for the algorithm used in Bitcoin (and other blockchains) and controls the generation of blocks.

The proof-of-work system is due to Adam backs hashcash from 1997. In Hashcash, computers must build a arithmetical proof of work before they can send information. Hashcash was developed to limit email spam and denial-of service attacks by connecting the flooding of a network with messages.

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