Compound (also known as Compound Finance) is a lending protocol founded by Robert Leshner. It was the first lending protocol to launch on Ethereum.
The Compound Protocol allows users to borrow crypto assets, using any other supported asset as collateral. It launched in September 2018 and later raised $25m from a16z and Paradigm in November 2019.
The protocol is thought to have pioneered the tokenization of assets with cTokens, yield bearing tokens which can grow in value.
In the summer of 2020 Compound started its liquidity mining program, giving out COMP token as an incentive for users to lend and borrow tokens on its platform. This incentive program attracted huge liquidity on the protocol and kickstarted the "Defi summer", which saw an enormous amount of liquidity poured over into DeFi. Later, more and more protocols followed with their liquidity mining programs to attract liquidity on their platform.