The technology revolutionizing how personal data is shared and protected is primarily based on blockchain. Blockchain is a decentralized, distributed ledger technology that enhances security and transparency in data transactions. By employing cryptographic techniques, it ensures data integrity, confidentiality, and immutability. With smart contracts, blockchain can automate processes while safeguarding personal information. This technology allows individuals to control their data access, promoting trust and privacy in digital interactions. As such, blockchain is poised to redefine data sharing and protection in numerous sectors, including finance and health care.