Blockchain is a decentralized digital ledger technology that records transactions across a network of computers in a secure, transparent, and immutable manner. Each transaction is grouped into a "block," which is then linked to the previous block, forming a "chain" of data. This structure ensures that once information is recorded, it cannot be altered without altering all subsequent blocks, making it highly secure and tamper-resistant.

Originally developed as the underlying technology for cryptocurrencies like Bitcoin, blockchain has since evolved to find applications in various industries, including finance, supply chain management, healthcare, and voting systems. Its key features—decentralization, transparency, and security—make it a transformative tool for enhancing trust and efficiency in digital transactions.