How exactly does facebook advertising work?

[Timothy]

If i were to advertise through Facebook how exactly does that work? Lets say i am trying to advertise for my local business here in the Philippines. How would myself or Facebook control whether or not the people who see my ads live in the Philippines? Also, is there a difference in price i have to pay to advertise to more people? I mean i have absolutely no clue how the advertising how Facebook works and i want to know everything about it in as much detail as possible, that would be great. Please help if possible. Thank you