AAVE is a decentralized finance (DeFi) platform that is built on the Ethereum blockchain. It allows users to lend and borrow various cryptocurrencies, earn interest on their deposits, and participate in various other financial activities.

On AAVE, users can deposit their cryptocurrency assets into "lending pools," which are pools of assets that are used to fund loans to other users. By depositing assets into these pools, users can earn interest on their holdings. AAVE uses a protocol called "Flash Loans" which allows users to take out loans and repay them within the same transaction, allowing for the creation of complex financial products and strategies.

In addition to lending and borrowing, AAVE also offers a range of other DeFi services, including stablecoin issuance, decentralized exchange (DEX) trading, and yield farming.