What is liquid swap?

Excuse me, could you explain what a liquid swap is in simple terms? I've heard it mentioned in the context of cryptocurrency trading, but I'm not entirely sure how it works. Is it a type of financial instrument? Does it involve the exchange of assets? And how does it differ from other types of swaps in the finance industry? I'm eager to learn more about this topic and how it relates to the world of cryptocurrency and decentralized finance.