The exchanges for buying and selling cryptocurrencies can be divided into two types:

Centralized exchanges are like the 'big counter' at a bank managing money. You have to deposit your coins into the platform account, and all transactions are matched through the platform, similar to how you pay at a supermarket checkout. The advantage is convenience; beginners can trade with just a few clicks, but the downside is that your funds are in someone else's hands—if the platform is hacked or runs away, you could lose everything.

Decentralized exchanges are more like directly exchanging items with your neighbors. You don't have to give your coins to anyone; you trade directly with others through smart contracts (automatically executed programs), and your coins always stay in your own wallet. It's like completing a transfer via WeChat; it's secure but a bit troublesome: you have to research the contract address yourself, the transaction speed may be slow, and sometimes the price can fluctuate (slippage).

In simple terms: the former is suitable for beginners who want to save trouble, while the latter is for 'tech-savvy' individuals who want to have control over their assets.