Blockchain is a distributed database or ledger shared among a computer networks nodes. It is a method of recording information that makes it impossible or difficult for the system to be changed, hacked, or manipulated. A blockchain is a constantly growing list of records, called blocks, that are linked and secured using cryptography. Each block contains a set of data, and the blocks are linked together in chronological order to form a chain of information.

The key features of blockchain include:

• Decentralization: Blockchain is a decentralized system, meaning that it is not controlled by a single entity or organization. Instead, it is maintained by a network of nodes that work together to validate transactions and add new blocks to the chain.

• Security: Blockchain uses cryptography to secure the data stored in each block. Once a block is added to the chain, it cannot be altered or deleted without the consensus of the network.

• Transparency: Blockchain is a transparent system, meaning that all participants in the network can see the data stored in each block. This makes it easier to track transactions and ensure that they are valid.

Blockchain technology has many applications beyond cryptocurrency, including supply chain management, voting systems, and digital identity verification. It is a constantly evolving field that offers an increasingly popular channel for online transactions and varied applications.