Blockchain is a distributed, decentralized digital ledger that is used to record transactions across many computers in a secure and transparent way. Each computer in the network, or node, maintains a copy of the ledger, which is constantly updated with new transactions.
The ledger consists of blocks of data that are linked together in a chain, with each block containing a unique digital signature called a hash. Once a block is added to the chain, it cannot be altered or deleted, providing an immutable record of all transactions that have taken place on the network.
Blockchains are typically used to record transactions involving cryptocurrencies, such as Bitcoin or Ethereum, but they can also be used for a wide range of other applications, such as supply chain management, voting systems, and digital identity verification.
The decentralized nature of blockchain technology makes it resistant to tampering and hacking, as there is no central point of control that can be targeted by attackers. This makes blockchain a secure and trustworthy way to record transactions and exchange value without the need for intermediaries like banks or governments.