Crypto lending works by taking crypto from one user and providing it to another for a fee. The exact method of managing the loan changes from platform to platform. You can find crypto lending services on both centralized and decentralized platforms, but the core principles remain the same.
You don’t just have to be a borrower, either. You can passively earn an income and gain interest by locking up your crypto in a pool that manages your funds. Depending on the reliability of the smart contract you use, there is usually little risk of losing your funds. This could be because the borrower put up collateral, or a CeFi (centralized finance) platform like Binance manages the loan.