Aave is an algorithmic money market wherein loans are offered from a pool instead of being individually matched to a lender.
Since, it's based on the ethereum platform, the programming language used is Solidity.
Aave permits its users to get loans in a different cryptocurrency than they deposited. For instance, a user may deposit Ethereum (ETH), then withdraw litecoins to deposit into Yearn finance (YFI) to receive a regular yield.
Some of the features Aave Platform has
Flash loans: In case when there is unused liquidity within the pool then borrowers take out uncollateralized loans and then return the loan as part of the same transaction – with a 0.09% fee.

Rate switching: Rate switching service is formulated in order to address the volatility of the crypto markets wherein borrowers are allowed to either lock in the interest rates of their loans or choose to stick with floating rates.