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Proof of Work

A consensus mechanism where miners compete to solve a computational puzzle to earn the right to add the next block.

FBFenwei BianAuthorVZVictor ZhouEditorJuly 2, 2026
  • glossary

Proof of Work (PoW) is a consensus mechanism in which miners compete to be the first to find a hash value below a target threshold, repeatedly hashing candidate block data until one succeeds. Finding a valid hash is deliberately expensive — it requires real computing power and electricity — while verifying a found solution is cheap, so the cost of the search itself is what deters attackers from rewriting history. Nodes treat the chain with the most accumulated work as the correct one, and a transaction becomes more irreversible as more blocks are mined on top of it, a property called probabilistic finality. Bitcoin introduced PoW in 2009 and remains its largest deployment; pre-2022 Ethereum also used it before switching to Proof of Stake. PoW's high energy use is the main trade-off weighed against newer consensus mechanisms securing blockchain networks today.

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Contributors

Fenwei Bian

Software Developer & Writer • Namefi
Author

Fenwei Bian is a software developer in her thirties who spends her working hours in pull requests and her weekends with her hands in soil or sawdust. Years of open source on GitHub taught her that names are interfaces: a good one is clear, honest about what it does, and kind to whoever has to use it next.

She gardens because it rewards patience and punishes wishful thinking, and she does woodwork because a joint either fits or it doesn't. Both habits show up in how she writes about naming — measure twice, check the source, and don't sand over a rough spot and hope no one notices.

For Namefi she writes about how domain markets actually move, the practical trade-offs of tokenizing and flipping names, and picking a domain you'll still be glad you own in twenty years.

GitHub

Victor Zhou

Founder & Standards Editor • Namefi
Editor

Victor Zhou is a technology founder and standards editor focused on digital identity and trust. He founded Namefi, edits Ethereum Improvement Proposals, and previously led smart-contract architecture work at Google Labs.

His work sits at the intersection of naming, ownership, and the systems people use to establish identity online. That perspective makes him especially interested in the way names move between personal meaning, public recognition, and digital infrastructure.

For Namefi, Victor edits and writes about domains as durable digital identity: how names become ownable onchain assets, how tokenization changes custody and trust, and what naming can learn from the systems people use to establish identity online.

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