Foundations · 04 / 86
Consensus
A network agrees on one history. That agreement is what people mean when they say the chain cannot be quietly edited by one company.
Proof of work
Miners spend electricity to propose the next block. Rewriting old history means outspending the rest of the network. That is expensive. It is not impossible.
Proof of stake
Validators lock coins for the right to propose blocks. Cheating can cost them that stake. The people with the most stake have the most say.
Agreement is not fairness, and it is not a guarantee your coins are safe from a bug, a scam, or your own lost key.
Check yourself
Does consensus stop a scam token?
No. The chain can agree that a scam transaction happened.
After this you can explain, in a sentence, how a chain picks one history, and what that does not protect.
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