Nick Szabo, the cryptographer who in 1998 invented the digital currency “Bit Gold,” coined the term “smart contract” in the early 1990s. In a 1997 paper, he said smart contracts “combine protocols with user interfaces to formalize and secure relationships over computer networks.” The system eliminates the need to pay for and trust third parties like auditors, accountants, lawyers, and notary publics, as the agreements are executed through a computer program. The humble vending machine is a primitive precursor to smart contracts, Szabo wrote in the paper.