An overview of Blockchain. Source: Rosic 2016.

Blockchain is an open immutable distributed ledger without centralized control. The ledger is maintained and validated by a peer-to-peer network of computers. Such a ledger could contain any digital asset of value such as cryptocurrencies, land records, birth certificates, insurance claims, concert tickets, the source of diamonds, etc.

Because digital assets can easily be copied, we need a system that prevents fraud. Traditionally, banks, government bodies and private institutions serve as trusted intermediaries. Blockchain aims to bypass them. It does this using cryptography. No one can tamper transactions recorded in the blockchain due to high computation costs. We may therefore say that trust is established implicitly via cryptography.

Blockchain was initially used to create and transact a cryptocurrency called Bitcoin. Today, it's anticipated that blockchain can be used for diverse applications and it's set to revolutionize multiple industries.