proof of work

Syllable breakdown

Dictionary meaning

the original blockchain consensus mechanism, introduced by Satoshi Nakamoto in the Bitcoin white paper of 2008, in which network participants known as miners compete to solve computationally expensive cryptographic hash puzzles to earn the right to add the next block to the blockchain and receive a block reward; the difficulty of the puzzle is automatically adjusted so that a new block is found approximately every ten minutes on the Bitcoin network; proof of work provides strong security guarantees because attacking the network would require controlling more than fifty percent of the total computational power, an enormously costly undertaking; however it is criticised for its massive and growing energy consumption — Bitcoin mining consumes electricity comparable to a medium-sized country — which has prompted many newer blockchains to adopt proof of stake instead