Hmm, I started programming around 1991, but didn't take it seriously until around 1997.

I haven't gone through this class, but it appears to cover the basics of programming language topics: https://www.udacity.com/course/cs262

And I like this book: http://mitpress.mit.edu/books/essentials-programming-languag...

You can get much, much deeper into this topic, but skimming the surface a bit was really all I was suggesting, unless you have interest in programming language design in particular.