About nodes and validators:
Archive nodes store the complete state data for every historical block in addition to what full nodes store, so they require much more disk space than full nodes.
In addition to running a node, validators must propose blocks and vote according to the rules. Being offline for an extended period can result in part of their balance being deducted, while misconduct can result in their stake being slashed.
$ETH 2396.62(+3.33%)