The technology that uses blockchain for secure transactions is known for its application in cryptocurrency, particularly Bitcoin. Blockchain is a decentralized digital ledger that records transactions in a transparent and immutable manner. Each block in the chain contains a list of transactions, which are cryptographically secured, ensuring data integrity and reducing the risk of fraud. This technology is not only limited to cryptocurrencies; it's also being explored for various applications across industries, such as supply chain management and contract management.