Proof of Work
The original consensus algorithm: miners spend computing power to solve puzzles, securing the network and making tampering expensive.
Proof of Work (PoW) secures a blockchain by requiring real physical work — electricity and hardware — to produce each block. Miners compete to solve a computational puzzle; the first to solve it proposes the next block and earns the block reward.
Why it decentralizes
PoW lets anyone with hardware participate: blocks are won by hashrate, not by permission. Rewriting history would require outspending the entire network’s computing power, which is why Bitcoin’s ledger is considered the most tamper-proof database ever built.
Trade-offs
PoW consumes large amounts of electricity. Its rivals — Proof of Stake and others — trade that energy cost for different trust assumptions. W3D audits measure how distributed hash power actually is.
Related terms
Mining, Hash, Bitcoin, Consensus Mechanism, Block