Cryptography is the study and practice of sending secure, encrypted messages between two or more parties. Cryptography is not to be confused with cryptocurrency, which is a digital or virtual currency. Cryptocurrencies use cryptography to allow transactions to be secure, anonymous, and “trustless,” which means you don’t need to know anything about a person to safely make transactions with them – and you don’t need bank, credit-card company, government, or any other third party in the middle – a central theme in decentralised finance (DeFi).