I wanted to learn the basics of OOP (classes and objects) back when C++ first appeared, but the topic was too heavy and too dry - and I was young.

A magazine article (remember those things?) described it using post office analogies, including a postal train. It just clicked.

I have no idea what magazine or writer, or why that set of analogies worked when there are far simpler explanations for classes and objects, but I owe my career to that article (and my lack of friends in high school .. but it's all good!)