Food should be cooled down before being put in the refrigerator?

Is it better to put cold food in the refrigerator or serve it while it's still hot?
In daily life, many people habitually stuff uneaten food, various fruits, and fresh produce into the refrigerator, believing it to be a safe and a surprisingly large container for food… But is that really the case? Let's find out!
Leftovers are often stored in the refrigerator, a common occurrence in daily life. But should they be put in while still hot, or after they've cooled down? Most people would probably choose the latter, but I'm here to tell you: put them in while they're still hot! Below are three common misconceptions about refrigerator use; see if you have any of these little obsessions.