Uniswap is a decentralized exchange on the Ethereum blockchain, enabling users to trade cryptocurrencies directly from their wallets. Its automated market maker (AMM) model eliminates the need for traditional order books, enhancing accessibility and liquidity. Uniswap's simplicity and wide range of supported tokens make it a popular choice in the decentralized finance (DeFi) space, despite potential concerns like high gas fees during periods of network congestion.