Blockchain

Blockchain is basically a database technology (over a computer network) that doesn’t allow re-write / update or deletion of data that has been committed to the series of data / records stored in it (referred to as blocks). This means it’s a write once, read only distributed database technology.

The method of linking different blocks of data together (referred to as the chain) is a technique called “distributed consensus”, which is a way of saying that multiple different entities (in this case computer nodes) within the blockchain network participate in a process of agreeing that the records within each dataset are true (or false) based on checking of cryptographic algorithms (called hashing). This ensures that once data is communicated, stored and distributed within a blockchain network, it is consistent, secured and very difficult to modify. These components are the underlying characteristics that define a blockchain.