How does Dex trading work?

Can you explain, in simple terms, how decentralized exchange (DEX) trading functions? How do traders go about buying and selling digital assets on a DEX platform? What are the key differences between DEX trading and traditional centralized exchanges? Are there any risks or benefits associated with DEX trading that traders should be aware of? Additionally, what role does blockchain technology play in enabling DEX trading, and how does it contribute to the security and transparency of the trading process?