A validator in blockchain refers to a node or participant in the network that is responsible for verifying the authenticity and accuracy of transactions and blocks.
Validators are typically chosen based on their computing power and reputation, and they use consensus algorithms such as Proof-of-Work or Proof-of-Stake to reach an agreement on the state of the blockchain.
In a proof-of-stake blockchain, validators are selected based on the amount of stake they hold, or the number of tokens they have invested in the network. This incentivizes validators to act in the best interest of the network and to avoid malicious behavior.
Validators are also responsible for adding new blocks to the blockchain, which contain the validated transactions. This process involves verifying the transactions and ensuring that they follow the rules and protocols of the network.