Blockchain

Blockchain consists of blocks that hold information. The blocks are stored on a network of computers and servers anywhere in the world.

Information on blockchain is written in code. Different blockchains amount to different information, for example, the cryptocurrency Bitcoin has one blockchain.

There are two aspects that make blockchain attractive to use.

Blockchain is immutable. Each information block has a time-stamp and an individual hash key [a code]. One block holds both its own hash key and the previous one’s, this way they stay connected [chained]

Blockchain is also distributed peer to peer, meaning that they are democratised and open source. Anyone who joins gets a copy of the blockchain. The more participants, the more reference points or “backups” there are.

New or changed blocks are verified by all the copies, e.g. no central authority is needed for verification.

It makes it extremely hard to hack a blockchain since it is more or less impossible to a) modify all the connected blocks and b) alter every copy of that blockchain.

Fig. 12: Hamilton (2021) [edited by author(s)] Illustration of the concept of blockchain