Raydium is a decentralized exchange (DEX) and automated market maker (AMM) built on the Solana blockchain. It leverages the high-speed, low-cost capabilities of Solana to provide users with fast and efficient trading experiences. Raydium integrates with the Serum DEX, offering deep liquidity and access to a wide range of trading pairs. It supports features like yield farming, staking, and liquidity provision, making it a versatile platform for DeFi activities.