DeFi platforms are decentralized applications (DApps) built on blockchain technology that provide financial services without the need for intermediaries. They enable users to trade assets, lend, borrow, and earn interest through decentralized protocols. Popular DeFi platforms like Uniswap, Compound, and MakerDAO allow users to participate in financial activities such as liquidity provision and yield farming. These platforms use smart contracts to ensure trustless and transparent transactions, offering lower fees and faster execution compared to traditional financial services, while giving users full control over their assets.