Blockchain is a form of distributed ledger technology, a digital system in which data is recorded across multiple places at the same time. Unlike traditional databases, DLTs have no central administrator or centralised data storage. They are transparent because the data is visible and, because they are automatically replicated and impossible to be tampered with, they are secure.
The main difference between blockchain and other forms of DLT is the way data is stored as ‘blocks’ – new transactions are added to the existing ‘chain’ of past transactions, hence the name ‘blockchain’. It is impossible to delete or modify information on the chain due to the replication of blocks across various locations.
Blockchain is mostly associated with cryptocurrency Bitcoin. Due to the inability to tamper with transactions, advocates say this makes the currency more secure and safer than traditional systems. It is maintained by a network of people referred to as ‘miners’, who receive rewards for solving complex mathematical equations that enable transactions to go through.
However, one of the major problems that has come to light has been the presence of illicit material buried in the Bitcoin blockchain, linking it to the dark web.
Other blockchain platforms can offer things like smart contracts, which are automatically implemented when specific conditions from all interested parties are reached, cutting the time involved and the risk of mistakes. Another use could be storing medical records, as patients can be confident their information cannot be changed. The technology can also be used in supply chains, voting and has the potential to used for storing property records.
