What is DeFi?

Decentralized Finance (DeFi) replaces traditional financial intermediaries — banks, brokers, exchanges — with smart contracts on a blockchain. Key properties: permissionless (anyone can use it), composable (protocols can be combined like building blocks), transparent (all code and transactions are public), and non-custodial (you control your own funds). The total value locked (TVL) in DeFi protocols has grown from under $1B in 2020 to tens of billions. Major categories include: DEXs, lending/borrowing, stablecoins, derivatives, and yield aggregators.