Technically, objects never really make contact with each other. when you put something down on a table, or stand up on the ground there is a very very tiny gap between the object and the table, or your feet and the ground. This happens because the electrons in the atoms of both objects repel each other. This is what keeps us from going right through objects since most of matter is empty space. But if it's an electrostatic force, why do we only feel it upon "contact"? Well, while atoms are composed of charged particles, they are electrically neutral, and from and since the charge of an electron is so small, even with billions of them, unless they are very close together, the force they exert on each other is so very small it's insignificant.