Speedos or board shorts

Hey everyone I was curious about when you are obligated to wear swim wear what is your go to? Swim briefs or board shorts?
I love both. Briefs for the limited fabric and the closest thing to being naked, how ever I find they can be restricting. On the other hand I do enjoy wearing board shorts with nothing underneath and I find it to be very unrestricting however the extra fabric robs me of the felling of the wind and sun on my skin?
I look forward to hearing you responses