Abbreviation for centralized exchange. A marketplace where you can buy and sell crypto. You can create limitorders, meaning you can set a price at which you want to buy or sell. You can marketbuy, meaning you will buy at the current trading price. The fees are low, because trades don’t happen onchain, but on the database of the exchange.
You can keep your crypto on a CEX, the downside being you don’t have ownership of the coins, but the CEX does. Meaning if something happens and you can’t access the account/ cex, your coins are not accessable.
Trading onchain happens on a DEX