【Terminology】What do full nodes, light nodes, and validators each do?
Archive nodes store the complete state data for every historical block in addition to what full nodes store, requiring far more disk space than full nodes.
Validators do more than run nodes: they also propose blocks and vote according to the rules. They lose part of their balance if they are offline for an extended period, and can be slashed for misconduct.
On Ethereum, becoming a validator requires staking at least 32 $ETH .
Every reward comes with corresponding risks, so first understand how much you could lose in the worst case.