Did you know that thousands of years ago people didn’t use money? They exchanged products or services. For example, you’re a farmer that grows potatoes, and your farmer friend Will grows apples. When you need apples, you can offer him some potatoes in exchange. And he’ll agree because it’s also a win-win for him – he has too many apples and wants mashed potatoes for dinner. Uniswap decentralized exchange works the same way – you can exchange, for example, ETH crypto (potatoes) for DAI (apples).