I live on the Earth, home to humans. Every human I've met, heard, or read about has been pretty stupid about something. I can't imagine that I'd be the sole exception, so if I had to guess I'm not smart.

More to the spirit of the question, for me it has to do with programming. I love programming, I went to school for it and learned a ton. It really covers a wide breadth of applications, and you can make anything happen with a computer if you're determined enough. And, like any field, there's general knowledge as well as deeper specializations.

If you're not into programming, know that there's a divide in every application between what's called the Back End and the Front End. The front end is what the user interacts with, and ultimately is an interface for the back end which actually runs the application.

I don't know if it would still be considered accurate, but in school we'd joke about how the back end is more complex (more services to integrate with), and the front end is easier because it's all about look and feel. Generally speaking, people develop an affinity for one or the other and then further specialize based on that.

I can't seem to pick up a front end framework to save my life. The thing that the self-described smart kids called easier is wayyy more complicated than it looks. I have a lot of training, I'm skilled in multiple languages, and I can whisper the secret words that open up the database. But I don't know if I could Hello World my way through a React app if there was a gun to my head.