Every blockchain needs consensus: a way for thousands of independent computers to agree on what happened. Today there are two major systems — and this one decision says a lot about a network’s decentralization.

Proof of Work (PoW) — "show the work"

Miners race to find a number that fits the network’s target — actually solving a pointless math problem that’s expensive in electricity. Whoever wins proposes the next block (mining).

– Security comes from physical cost. Rewriting history means paying more electricity than the whole honest network. – Anyone can join with hardware. No permission. – Cost: enormous energy use. That’s the famous Bitcoin criticism, and the reason PoS was invented.

Proof of Stake (PoS) — "money at risk"

Validators stake real tokens as collateral. They’re chosen to propose/confirm blocks in proportion to what they’ve staked and risk losing it if they misbehave (“slashing”).

– Security comes from financial cost. Misbehave and you lose your stake. – Cheap to run — no racing hardware, just an honest machine. – Cost: it tends to concentrate power — the biggest pools attract the most stake, which is a real decentralization question.

Which is "more decentralized"?

Neither, on its own. Everything depends on *distribution*:

– PoW is decentralized if hash power is spread across many independent miners (and not a few giant pools). – PoS is decentralized if stake is spread across many independent validators (and not one liquid-staking provider).

That’s exactly what W3D measures — not “PoW vs PoS” marketing, but who actually holds the power. Try it on the decentralization terminal.

Next lesson: staking and earning on your crypto.