#CEXvsDEX101 , a centralized exchange (CEX) is a business that specializes in helping make transactions happen between two parties. In traditional finance, all businesses are centralized exchanges, for example banks (Goldman Sachs), stock trading apps (Robinhood), and payment processors (Visa). All centralized exchanges are trusted middle men. In crypto, there are centralized exchanges, but also decentralized exchanges (DEXs) which do not require a trusted third party.