To the OP:
Part of the problem is that many of the knowedgable experts on guns, aren't.
Many that work in sporting goods stores, selling guns, are functionally clueless; not becasue they're stupid, but because the boss said, "You're over in that department, today."
Many that own guns are not much better...unfortunately, knowledge of one facet does not always translate to others.
I consider myself fairly well informed about Trap and shotguns; I can give pertinent advice about the basics of rifle and handgun safety and shooting; I have a fairly good layman's grasp of Mass gun laws (though the IANAL discalimer is not alien to me). I'd not give advice about the subtleties of bullseye pistol, or long-range rifle.
My point? Read more than one book; ask more than one person; use more than one source. A lot of terms in the shooting world have different meanings, depending on context. And when, in a couple of years, you're the "resident expert" on gun stuff at your work.....remember that you don't know it all (nobody does!) and that a wrong answer is worse than no answer.
There's a wealth of info here...don't be afraid to ask....and since you're new, many of the questions that you'll pose are ones that have been asked and answered before....you may get an
or "facepalm" jpeg, but don't take it seriously. Most people here are pretty cool.
Welcome.