I prefer winning
Playing style

Depends what my opponent is doing :) If we're both attacking it makes me nervous. I'd actually rather defend and prove his attack was wrong in some way (if possible).
However if one of us is the attacker and one of us the defender, I'd rather be attacking. I choose this because a botched attack is more forgiving than a botched defense I'd say
what is positional?
Positional is where , instead of going straight for an attack or a defence , you slowly build up a better position and " strangulate" your opponent by leaving him with no good options. Great positional players are Anatoly Karpov and Jose Capablanca.
so kind of like attacking and defnding at the same time?
I would say more defensive as you improve your own position , rather than attack your opponents.

It completely depends on the board.
I would say I am offensive, but there are times when the best form of attack is to defend certain squares and pieces before you have the opponent where you want.
My most crucial form of play is more to do with wanting control of as much of the board as I can handle. Aggressive/defensive play have their roles for this goal.
Control the board, control the outcome. Usualy this requires some sacrifices and most I would say consider this offensive play.

I also agree that there's no universal choice of "attacking" or "defending".
You play the position that's at the board. If your opponent has a weakness - attack that weakness. If he doesn't, don't attack - there's no target, and you would waste moves or material; try to first create a weakness, or wait for one to appear. If you have a weakness, try to make sure your opponent won't be able to exploit it, or that exploiting it will cost him/her something else. If you have no weakness - try not to allow one.
Instead of choosing between an "attacking" or "defending" style, try to develop your ability to assess the position. If, while looking at a random chess position, you are able to say "White stands better", "Neither side can win", "Black can attack White's castle because it's weak", or something like that, you're half way towards choosing your style of play in that position, hence in all positions.
Develop your positional evaluation skills. They will tell you how to approach the position.
Here's an article from IM Jeremy Silman that can give you a possible approach to positional evaluation and its influence over game planning and move choice:
http://www.chess.com/article/view/how-to-evaluate-a-position

thanks waffle master. arctor, plz leave this forum
Arctor's comment was the best and most accurate so far. The ultimate goal in chess is to win by checkmating the oponents king, and you often don't get to choose between attack and defense if you want to reach that goal. In some positions, preffering to attack/defend is the equivalent of preffering to lose rather than win or draw.
You're also a fool if you think you can completely control discussion in this forum, even if it's your own thread.

well, the topic wasn't whether you prefer to win or lose, becuase that's just stupid. the topic was what your playing style is, and why you like to play that way

Arctor's comment was the best and most accurate so far. The ultimate goal in chess is to win by checkmating the oponents king, and you often don't get to choose between attack and defense if you want to reach that goal. In some positions, preffering to attack/defend is the equivalent of preffering to lose rather than win or draw.
of course you can choose whether you want to attack or defend! it just depends on the position as elona said. you can choose the positions, and everything is your opinion.
Do you prefer playing offensive, or defensive and why?