What is Blockchain ?

Blockchain is a decentralized and distributed digital ledger technology that records transactions across multiple computers. It was originally introduced as the underlying technology for cryptocurrencies like Bitcoin but has since found applications in various industries beyond finance.

At its core, a blockchain is a chain of blocks, where each block contains a list of transactions. These blocks are linked together using cryptographic hashes, forming a chronological and tamper-evident record of all the transactions that have occurred on the network. The decentralized nature of blockchain means that no single entity has control over the entire system, and the ledger is maintained collectively by all participating nodes in the network.

One of the key features of blockchain is its immutability. Once a block is added to the chain, it is extremely difficult to alter or remove the information within it. This makes blockchain a secure and trustworthy system for recording transactions and other types of data.

Blockchain relies on a consensus mechanism to validate and agree upon the state of the ledger. The most commonly known consensus mechanism is proof-of-work (PoW), used by Bitcoin, where miners compete to solve complex mathematical puzzles to add blocks to the chain. Other consensus mechanisms, such as proof-of-stake (PoS) and delegated proof-of-stake (DPoS), have been developed to address scalability and energy efficiency concerns.

Beyond cryptocurrencies, blockchain technology has been applied to various use cases, including supply chain management, healthcare records, identity verification, voting systems, decentralized finance (DeFi), and more. Its decentralized nature, transparency, and security make it appealing for applications where trust, accountability, and tamper-proof records are crucial.