A DEX, or Decentralized Exchange, is a type of cryptocurrency exchange platform that operates without a central authority or intermediary. Unlike centralized exchanges (CEXs), which are run by a single entity, DEXs facilitate peer-to-peer trading of cryptocurrencies directly between users through smart contracts or decentralized protocols on a blockchain.

DEXs allow users to trade cryptocurrencies in a decentralized manner, meaning that users retain control of their funds and trade directly from their wallets without the need to deposit their assets into the exchange. They often promote transparency, security, and privacy by eliminating the need for users to undergo Know Your Customer (KYC) procedures in many cases.

DEXs come in various forms, including automated market makers (AMMs), order book-based exchanges, and hybrid models. Examples of popular DEXs include Uniswap, SushiSwap, and PancakeSwap.