Blockchain in cybersecurity by providing decentralized, tamper-proof systems that protect sensitive data and digital identities. Its distributed ledger technology prevents unauthorized access and ensures data integrity, making it ideal for protecting critical infrastructure, IoT networks, and authentication systems. Smart contracts automate access controls, while cryptographic hashing safeguards records. Blockchain also helps detect malicious activity through immutable audit trails. Businesses are increasingly using blockchain to reduce cyber risks, prevent data breaches, and ensure compliance. Its decentralized nature makes it resistant to traditional cyberattacks, creating a powerful layer of digital defense.