Validators are individuals or entities responsible for confirming transactions and maintaining the integrity of a blockchain network. They play a crucial role in ensuring that all transactions are legitimate and that the network operates smoothly. Validators are often involved in processes like proof of stake or proof of work, where they validate new blocks of transactions. In a proof of stake system, validators are chosen based on the amount of cryptocurrency they hold and are willing to "stake" as collateral. This incentivizes them to act honestly, as they can lose their staked assets for malicious behavior. Overall, validators help secure and decentralize blockchain networks.