Each computer (node) in a blockchain network stores an identical copy of the distributed ledger. Because of its decentralized nature, no governing body or bank is required to keep tabs on financial dealings. A blockchain is a distributed, public, and immutable digital ledger or database that records transactions in a sequential and linked fashion. Blocks are collections of these individual transactions. Each block contains a set of transactions and a unique identifier called a "hash." Blocks are linked together in a chain whose hash includes the hash of the preceding block, hence the term "blockchain." Agreement Routines: Proof-of-work (PoW) and proof-of-stake (PoS) are two examples of consensus mechanisms used by blockchain networks to verify and agree on the ledger's data. These features guarantee that everyone in the network sees the same version of the ledger. The security provided by blockchain is well-known. Information in a block cannot be easily modified after it has been added to the chain due to cryptographic hashes and the decentralized nature of the network. All participants in a public blockchain can view all transactions taking place on the network. However, participants' identities are often disguised by using fictitious addresses. The consensus mechanism makes it extremely difficult to alter or remove a transaction once it has been recorded on the blockchain. Because of this immutability, the ledger can never be tampered with. Smart contracts, computer-executable agreements with predetermined terms, can be created on blockchain platforms like Ethereum. Smart contracts streamline and automate a number of operations. The use cases for blockchain technology extend far beyond the realm of digital currency. It's used in everything from supply chain management and healthcare to finance and voting systems for increased openness, safety, and productivity. Blockchain rose to prominence as the underlying technology for recording transactions in cryptocurrencies like Bitcoin. However, blockchain now has the potential to serve a wide variety of uses. As the world becomes more interconnected, blockchain technology has the potential to disrupt established industries while improving many facets of digital transactions, data management, and trust. As the technology develops, new applications emerge.