I've got a couple questions.

1. Is this open?

2. And this is a pretty big one. How exactly does magic work in the Harry potter universe? It seems to have no limit in what it can do. Just have a wand and bam, you could blow up the planet with the proper spell and besides the planet blowing up, you'd not even feel a little winded minus the physical exertion of flicking the wand. That always confused me.