An exchange is a marketplace where assets, such as commodities, stocks, and cryptocurrencies, can be bought and sold. Traders use the exchange to buy or sell assets. Traditionally, the exchange works in an order-book manner. For example, buyers place an order on the exchange specifying the type and quantity of the asset they want to buy and the maximum price they are willing to pay — a limit order. Sellers do the same. The exchange then matches the buy orders and sell orders. When a match is found, the deal is done and completes the transaction. Among decentralized exchanges (DEX), interestingly, a new type of exchange is very prevalent, the Automated Market Maker, AMM.