Why is blockchain important because it revolutionizes how data is stored and shared, offering decentralized, transparent, and secure systems. By eliminating intermediaries and allowing direct peer-to-peer transactions, blockchain reduces costs, enhances trust, and improves efficiency in industries like finance, supply chain, and healthcare. It enables immutability, meaning once data is recorded, it cannot be altered, increasing security. Blockchain also fosters innovation, supporting decentralized applications (dApps), smart contracts, and digital assets such as cryptocurrencies. Its ability to provide tamper-proof data and promote transparency makes it a transformative technology for various sectors.