blacklinemedia, thanks a lot for your answer!
I’ll consider the thing about the tags, but turns out I believe they’ll be used exactly in the way they were meant to be, except that I’m intending to use many, many of them.
So, in order for me to use the categories as you mentioned, it would be nice if I could let the reader see a page containing a list of categories; a sidebard widget wouldn’t be helpful in this case since there will be many. How can I, then, create a page (static) with a list of categories (and maybe with tags too), accessible by the reader?
??