Many know that the blockchain first rose to prominence as the technology behind the cryptocurrency Bitcoin. The 2008 Bitcoin whitepaper put forward a purely peer-to-peer electronic cash system that would allow online payments to be sent directly from one party to another without going through a financial institution. Since then, many different cryptocurrencies and various different blockchain protocols have emerged.
Despite the original intention behind its creation as a payment system, the blockchain, often described as a distributed ledger, is now being widely considered as a platform for distributed applications in different industries even beyond financial services.
The reason for this is that a blockchain is essentially a database shared across thousands of computers that is cryptographically secured. It is a natural evolutionary step from traditional centralized server networks to distributed computing. Every computer or device in a blockchain network receives an updated copy of the ledger, and any changes to the ledger are reflected in every copy in minutes or even seconds. Security is maintained cryptographically through keys, signatures and a consensus of validators.