How Does PoW Differ Fundamentally from Proof-of-Stake (PoS)?

PoW secures the network through energy expenditure and computational power (mining). PoS secures the network through economic stake, where validators are chosen based on the amount of currency they hold and are willing to "stake" as collateral.

PoW is about "work" to find a hash; PoS is about "holding" the asset and risking its loss (slashing) for malicious behavior.

How Does the Energy Consumption of Proof-of-Work Compare to Proof-of-Stake Consensus Mechanisms?
How Does the Energy Consumption of PoW and PoS Compare in the Context of Economic Security?
How Does Proof-of-Stake (PoS) Differ from PoW in Terms of Security and Energy Use?
What Are the Primary Security Trade-Offs between PoW and PoS?
How Does a Proof of Stake (PoS) Consensus Mechanism Differ from a Proof of Work (PoW) System?
What Is “Slashing” in a Proof-of-Stake System?
What Are the Key Differences between Proof-of-Work and Proof-of-Stake Consensus Mechanisms regarding Network Security?
How Did Ethereum’s Transition to Proof-of-Stake (PoS) Fundamentally Change Its Security Model?

Glossar