Introduction
Blockchain technology is a system of ensuring a secure, tamper-proof, and permanent record of transactions. The fundamental idea of a distributed secure ledger was invented in 2008 by Satoshi Nakamoto (Nakamoto, 2008). Initially, the technology created bitcoin, which verifies financial transactions without the requirement for a central authority, the federal reserve, a central bank, or other financial institution. Because the method of transaction verification involves a network of computers, rather than a single computer, it is very fault-tolerant. Any single computer can be added or removed from the network at any time without corrupting the ledger of transactions. Because the ledger is duplicated across all network computers, transactions are secure and immutable. A key feature of blockchain technology is that it is trust-less: transactions are processed by the network so there is no need to trust a single computer, database, or institution. The initial blockchain created bitcoin, which consists of a secure, immutable, distributed database of financial transactions. However, the technology has also been extended to create a system of secure, immutable, distributed computer programs allowing the creation of smart contracts and artificial intelligence (Buterin, 2015).