Proof of work
Proof of work makes block production a costly search. In Bitcoin, nodes choose the valid chain with the most accumulated work, not simply the most blocks.
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A USEFUL DISTINCTION
Proof of work vs proof of stake
Two ways to weight participation in choosing a shared history.
| Look at | Proof of work | Proof of stake |
|---|---|---|
| Scarce resource | Computational work supported by hardware and energy. | Assets committed under the protocol’s consensus rules. |
| Participants | Miners propose candidate blocks; nodes enforce validity. | Validators propose and attest; nodes enforce validity. |
| Economic exposure | Operating costs and hardware value. | Capital exposure, penalties, and potentially slashing. |
| History selection | Bitcoin selects the valid chain with most accumulated work. | Chain-selection and finality rules depend on the PoS protocol. |
| Failure concerns | Hash power concentration, censorship, and reorganizations. | Stake/operator concentration, correlated faults, and finality failures. |
Bitcoin developer documentation contributors · Bitcoin developer guide: Mining ↗Checked 13 Nov 2026Bitcoin developer documentation contributors · Bitcoin developer guide: Block Chain ↗Checked 13 Nov 2026Ethereum.org contributors · Proof-of-stake ↗Checked 13 Nov 2026Ethereum.org contributors · Ethereum staking ↗Checked 13 Nov 2026Ethereum.org contributors · Ethereum transactions ↗Checked 13 Nov 2026Bitcoin developer documentation contributors · Bitcoin developer guide: P2P Network ↗Checked 13 Nov 2026
THE KEY DISTINCTION
What to carry forward
The consensus mechanism does not replace transaction validity rules. An invalid spend cannot be made valid merely by a miner or validator proposing it.
MAKE IT CONCRETE
A worked perspective
Bitcoin and Ethereum use different histories, rule sets, and settlement assumptions; a single confirmation-count rule cannot be transferred between them.
Follow the underlying mechanisms
Proof of stake
Proof of stake assigns consensus influence using committed assets and protocol rules. Rewards compensate participation; penalties make certain failures costly.
Finality and confirmations
Finality describes the strength of settlement under a network’s assumptions. A transaction can be visible, included and successful before it is considered final.