A validator verifies transactions in a proof-of-stake network. Validators lock up coins as collateral, propose new blocks, and attest to the validity of blocks proposed by others. If they do their job honestly, they earn rewards. If they cheat or go offline too long, they lose part of their stake. That penalty is called slashing. Validators are the proof-of-stake equivalent of miners. They secure the network, but they do it with capital instead of electricity.

Running a validator requires technical skill. You need a reliable server, a stable internet connection, and enough staked coins to meet the network's minimum. Ethereum requires 32 ETH to run a solo validator. That is a significant barrier. Delegation lowers it. Small holders can delegate to a validator and share the rewards without running any hardware. The trade-off is trust. You are trusting the validator to behave honestly. If they get slashed, your delegated stake gets slashed too. Choose a validator with a good track record, reasonable commission, and no history of downtime. Validators are the backbone of proof-of-stake security. Without them, the chain stops.

Validator responsibilities

• Propose blocks — create new blocks when selected
• Attest — vote on the validity of other blocks
• Stay online — downtime leads to penalties
• Act honestly — misbehavior leads to slashing

Validators are not miners. They do not compete on hash rate. They compete on reliability and reputation.