1. Uniswap

2018 saw the release of Uniswap, which was groundbreaking. It was quite an accomplishment to be able to swap ERC20 tokens on the Ethereum blockchain without using an order book. Instead, Uniswap used smart contracts to enable peer-to-peer trading between users, making it decentralized and peer-to-peer.
2. Curve Finance

Curve is a decentralized cryptocurrency exchange that operates on the Ethereum network and primarily offers liquidity to ERC-20 tokens like stablecoins and wrapped tokens like wBTC and tBTC. Curve, an AMM (Automated Market Maker), offers consumers a decentralized method of exchanging various cryptocurrencies via liquidity pools. Curve, on the other hand, differs from other AMM systems in that it favors stability over speculation and volatility.
3. PancakeSwap

Popular DeFi cryptocurrency exchange Pancakeswap uses smart contracts to automatically execute trades on its site. This DEX, which functions similarly to Uniswap and utilizes the Binance Smart Chain (BSC), enables users to swap and exchange assets by offering liquidity pools. Users can utilize Pancakeswap’s proprietary token, CAKE, for yield farming, staking, and voting on governance protocols.