09
About a minute.
Last time:contracts are vending machines.
How the network stays honest
Ethereum no longer mines with electricity. Validators lock ETH, propose blocks, and lose stake if they cheat.
Try it
One beat: lock, cheat, watch it burn.
Maya
unlocked
0.00 ETH at stake
Maya locks 32 ETH. That bag is the cost of cheating.
Bitcoin-style mining asked computers to burn energy on a puzzle. Ethereum did that too, until September 2022 — “the Merge” — when it switched to proof of stake. Instead of racing fans and GPUs, people lock ETH as collateral and take turns proposing blocks.
A solo validator posts 32 ETH and runs software that stays online. Most people join a pool or a liquid staking service so they do not have to. Validators vote on which block is the head of the chain. If they sign two conflicting histories, or go offline for a long time, the protocol can take some of their stake. Honesty is cheaper than cheating.
No system is magic. A majority of stake acting together could, in theory, censor or reorganize. The bet is economic and social: that much ETH, held by many independent parties, is hard to coordinate into an attack — and easy to notice.
You do not need to become a validator to use Ethereum. You should know why you can trust a block explorer: a large, bonded set of operators has money on the line for the same history you are looking at.
Takeaway
Proof of stake replaces energy races with collateral. Validators can earn fees — and can be punished for breaking the rules.