how do you know the difference between positional play and attacking play

Is it just me, or can you be a positional, attacking player? Alphazero demonstrated this in 2017 or something when he demolished Stockfish

KetoSaiba gave the most thorough explanation, it's not super simple concept where this is A and this is B, but if I had to sum it up in a simple manner I would say that "attacking play" is when you go and attack your opponent's king and try to go for checkmate in the middle game. This can be done in more than way, for example, tactics with sacrifices, pawn storms, etc...)

Whereas positional play is when you play more solid, slowly improving your position, controlling more space and more squares and squeezing your opponent until you can win a pawn and then grind an endgame to promote that pawn to a queen and win an endgame.

Now keep in mind this is an overly simplified explanation so you can grasp the basics of what it is... but that is not necessarily how it happens, they're interchangeable, sometimes you're playing positionally, very solid and slowly building up your position and your opponent plays a move that allows you to initiate an attack

As some master said some 100 years ago "tactics flow from a superior position" 

That was Bobby Fischer

The essence of positional play is to prevent tactics.

100% you can. You can dominate a specific file or diagonal where you expect the king to go and having the king go anywhere else would be much more troublesome (ie. a fully developed king side ready to castle but with a lackluster queen side, and your opponent dominates the most important files and diagonals on the king side)

When you have nothing to do, there's probably a lot you can do that you're not considering. Double-check how safe the king is and try to launch an attack if it's not safe. Look at your worst piece and aim to get it to a better square. Maybe your pieces are already well-developed, but they're the ones with nothing to do and not you. You could have a bad pawn structure you want to improve, but that's a little complex. The list goes on.

You can read "My System" by Nimzovich, where he explains positional play.

Here is an example game of positional play

https://www.chessgames.com/perl/chessgame?gid=1102400 

They don't just pop out of thin air. This is why I believe that it's 99.9% tactical: the other 00.1% is the positional play that makes the tactics.

Nice that you recognize chess isn't 100% tactical, but you will come to realize that as your rating improves, more and more of your games will be more positional. Chess is nowhere near 99% tactics though. Even beginners utilize opening principles and some basic endgame patterns - this is not tactical. 

oh yeah, thanks

Positional play = defensive play, no frontal assault, safety first always, mind your pawn structure etc.

'Positional' is such an ambiguous term, call it for what it is... 'defensive'.

AlphaZero would like to know your location.

Positional play is the gathering of small advantages which may then lead to a direct attack or a winning endgame. Positional play is not necessarily defensive, eg see the games of Anatoly Karpov. Attacking play usually means playing sharp openings, seizing the initiative at the earliest opportunity and playing for mate (which sometimes means settling for a winning endgame. Really good players play both positional chess and attacking chess equally well, eg Carlsen or Caruana.