Do we use these reserved word, or not?

Question

I was wondering whether we use these reserved words or not. I'm confused, because according to the side note, it says that we will used these later on. A clarification would be of a great help please.

Answer 1

Reserved words are words that mean something specific to the programming language. Ex: var is a reserved word used to make variables. for and while are used to make loops.
You can't use these words as variable names, because they're already "taken"/reserved to do something else. You'll learn when to use them.