A decentralized exchange (DEX) is a cryptocurrency exchange that operates on a blockchain network. DEXs are designed to be decentralized, meaning that they are not controlled by any single entity or organization. Instead, they rely on smart contracts to facilitate trades between users directly, without the need for an intermediary. This allows for greater security, transparency, and autonomy in trading. However, DEXs generally have lower trading volumes and fewer trading pairs compared to centralized exchanges.