A blockchain is a decentralized, distributed digital ledger that records transactions across a network of computers in a series of interconnected blocks. Each block contains a set of transactions, a timestamp, and a unique cryptographic hash that links it to the previous block, forming a tamper-resistant chain. This structure ensures data integrity because altering any block would require changing all subsequent blocks. Blockchains are the foundational technology behind cryptocurrencies and are also used in supply chain management, voting systems, and other applications requiring transparent, immutable recordkeeping.
Example
“Every Bitcoin transaction is permanently recorded on the blockchain, allowing anyone to verify payment history using a block explorer.”