A Blockchain is a distributed database or ledger that is shared among the nodes of a computer network. As a database, a blockchain stores information electronically in digital format. Blockchains are best known for their crucial role in cryptocurrency systems, such as Bitcoin, for maintaining a secure and decentralized record of transactions. The innovation with a blockchain is that it guarantees the fidelity and security of data without the need for an intermediary party to maintain trust. This feature makes blockchains ideal for applications where transparency and trust are essential, such as supply chain management or voting systems.A blockchain is a digital ledger of all cryptocurrency transactions. It is constantly growing as "completed" blocks are added to it with a new set of recordings. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. Bitcoin nodes use the block chain to differentiate legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere.The use of a blockchain removes the need for a third party to verify transactions, as well as the need for the party to maintain trust. This makes blockchains ideal for applications where transparency and trust are essential, such as supply chain management or voting systems.