Blockchain - the technology of the future

Blockchain is a continuously growing list of records, called blocks, which are linked and secured using cryptography. It acts as a distributed public ledger. Each block typically contains a hash pointer which links it to a previous block, a timestamp, and transaction data. By design, blockchains are inherently resistant to modification of the data. They are typically managed by a peer-to-peer network collectively adhering to a protocol for validating new blocks. Once recorded, the data in any given block cannot be altered retroactively without the alteration of all previous blocks, which requires collusion of the network majority (51%).
Blockchains are secure by design, and are an example of a distributed computing system with high Byzantine fault tolerance. Blockchains have achieved decentralized consensus. This makes them potentially suitable for the recording of events, medical records, identity management, transaction processing, documenting provenance, food traceability, and kinds of other record management.

The first blockchain was conceptualised in 2008 by an anonymous person or group known as Satoshi Nakamoto, and implemented in 2009 as the public ledger for all bitcoin transactions. The inclusion of blockchain in the Bitcoin system made it the first digital currency to solve the double spending problem without resorting to a trusted authority or central server. Blockchain is the main innovation of Bitcoin.