Aave (AAVE) is a decentralized finance protocol that aims to facilitate lending and borrowing of cryptocurrencies. The name Aave, meaning "ghost" in Finnish, was adopted in September 2018, replacing its original name, ETHLend, which was launched in November 2017. AAVE tokens serve dual purposes on the platform: they provide holders with discounted fees and act as a governance token, allowing owners to participate in the future development of the protocol. The protocol was founded by Stani Kulechov, a serial entrepreneur with a background in law and programming, who sought to create a lending application on the Ethereum blockchain.

Aave operates by allowing users to lend and borrow approximately 20 different cryptocurrencies. Lenders receive yields by depositing digital assets into specially created liquidity pools. Borrowers, on the other hand, can use their crypto as collateral to take out a flash loan using this liquidity. One of Aave's unique features is its "flash loans," which are uncollateralized loan options that must be paid back within the same transaction. Additionally, Aave allows borrowers to switch between fixed and variable interest rates, providing flexibility based on market conditions.

Aave seeks to cater to individuals already engaged in the cryptocurrency community, offering a range of services beyond Ether lending. Its unique selling points include the ability to lend and borrow in a variety of cryptocurrencies, offering users a variety of choices. The platform's flagship product, "flash loans," are the first uncollateralized loan options in the DeFi space, providing a specific use case. Furthermore, the ability to switch between fixed and variable interest rates allows borrowers to switch between fixed and variable interest rates during volatile market conditions.

Aave, initially known as ETHLend, was launched in November 2017 by Stani Kulechov. The platform underwent a rebranding in September 2018, adopting the name Aave. An initial coin offering was held in November 2017, raising $16.2 million by selling one billion AAVE tokens. In July 2020, Aave conducted a token swap, swapping the 1.3 billion AAVE tokens in circulation for the newly minted AAVE cryptocurrency at a ratio of 1:100. Aave's open-source protocol is built on Ethereum, a blockchain that transitioned from Proof-of-Work to Proof-of-Stake.