>I have been working on this warehouse to create a place for photography enthusiasts. In it, I want to have a gallry space. My question is that if there is any special ways to build gallery walls. Are they just simply drywall?<

I would think you should use drywall, but use a plywood "skin" outside the wall. Think about it, you're going to be hanging up, taking down, hanging up, taking down framed photos, re-hanging them, hammering in new nails, taking out old screws, etc. I think drywall would crack and break under situations like this. Use a plywood skin, do a good painting job on top of it of a really beautiful, high quality white paint and I think you've got it from there.