Obviously it makes sense when considering the force of weight and the fact that the object is not moving up or down, but what is it composed of? What I mean is, the ground you are standing on is made of molecules bonded through the electromagnetic force, right? But those bonds are parallel to the ground, and presumably they exactly offset each other, which seems to me to mean that there is no possible way for them to exert a force vertically when you stand on those molecules. Unless it's the molecules of your feet that are getting electrically repelled by the ground? But, aren't these forces from protons and electrons essentially cancelled so that both you and the ground are electrically neutral? And doesn't the electrical force decrease by the square of distance? But how close are you really to the molecules on the floor when you stand on it? Is that close enough for the electrons from your feet to be repelled by the electrons from the floor in just the right amount to overcome the downward force of your weight? And then how is it that the weight + the protons in your foot being attracted to the electrons on the ground not stronger than the force of the electrons on the ground repelling the electrons on your feet? I know this is kind of all over the place, but if anyone could explain in some detail exactly how normal forces work (in particular, why you don't fall through the floor) in terms of a summation of component forces from the matter in question itself on a molecule-detail-level I would be very thank full.