Blockchain is a decentralized and distributed digital ledger technology that records transactions across multiple computers in such a way that the registered transactions cannot be altered retroactively. This technology underpins cryptocurrencies like Bitcoin and Ethereum, but its applications extend far beyond digital currencies. Each block in a blockchain contains a list of transactions, a timestamp, and a cryptographic hash of the previous block, linking them together in a chain. This structure ensures that once a block is added to the chain, it is extremely difficult to change, providing a high level of security and integrity. The decentralized nature of blockchain means that no single entity has control over the entire chain, reducing the risk of fraud and manipulation. Beyond cryptocurrencies, blockchain technology is being explored and implemented in various industries for its potential to enhance transparency, efficiency, and trust. In supply chain management, blockchain can provide an immutable record of product provenance, helping to verify authenticity and traceability. In finance, it can streamline processes such as cross-border payments and smart contracts, which automatically execute agreements when predefined conditions are met. Additionally, blockchain is being used in areas like healthcare for secure patient data management, in voting systems to ensure election integrity, and in intellectual property to protect digital rights. Despite its promise, blockchain faces challenges such as scalability, energy consumption, and regulatory hurdles, which need to be addressed for broader adoption.