A blockchain is a decentralized, distributed database that maintains a continuously growing list of records called blocks. Each block contains a timestamp and a link to the previous block, forming a chain of blocks.

One of the main features of a blockchain is that it is immutable, meaning that once data is written to a block, it cannot be altered. This is because each block in the chain includes a cryptographic hash of the previous block, which acts as a unique fingerprint. If any data in a block is changed, the hash of that block will also change, making it immediately apparent that the block has been tampered with.


Blockchains are often used to create secure and transparent systems for storing and exchanging data and value. They are particularly well-suited for applications where the security and integrity of the data is important, such as in financial transactions or supply chain management.

One well-known example of a blockchain is the Bitcoin blockchain, which is used to track and verify Bitcoin transactions. However, blockchains have many other potential uses beyond cryptocurrency, including in areas such as voting systems, identity verification, and medical records