Basically, an electrostatic charge is a situation where electrons have been stipped off or added to a body. This is a very simplistic model, but it is easy to understand and i…s arguably the most common one in the real world. Let's look at it..
Electrons hang around parent atomic nuclei. But they are suseptable to being moved. Certainly they shift around in chemical reactions, but let's take a common example using something that is fairly chemically stable - kitchen plastic wrap..
Ever pull some plastic wrap off the roll and have it "fold up" on itself? Darn frustrating. But anyone who removes some plastic wrap from a roll like that is participating in an experiment involving electrostatics. The simple act of pulling the wrap off the roll causes electrons to move because you've given them energy. And because the plastic is a pretty good insulator, the electrons can't "get back" to where they were. The electrons have been given energy to move and have been moved by pulling the plastic off the roll. You've separated charges - created static electricity. And now there is an electrostatic charge acting on the plastic and causing it to attract itself and fold up..
If we electrostatically "borrow" electrons from an atom, that atom is left with a positive charge. But generally that atom isn't going anywhere. It certainly isn't in that plastic wrap. The electron, however, can be moved with ridiculous ease. We've separated charges, and now have an electrostatic charge between the atom and the electron we removed. If we do this on a large scale by shuffling across a rug on a dry (low humidity) day, we get jolted reaching for the door knob. We separated charges with the simple friction of our feet on the rug. This built up an electrostatic charge, and we "got neutralized" by reaching for the door knob. As long as the materials involved in charge separation aren't too conductive, the charges can't "get home" and a charge will build up. (You can build up a charge rubbing a rubber rod with rabbit fur, but you can't really build up a charge rubbing an aluminum rod with fur.).
Moving air, wind, creates friction that can separate charges. The movement of air and moisture in clouds separates charges and builds up an electrostatic charge. You already know where this is going. Zap! Lightning. Cloud-to-cloud, or cloud-to-ground, or ground-to-cloud. Whatever the charge can "work out" to move toward a more neutral state, it will. In the case of lightning, the voltage (difference of potential or electromotive force) will be so great that air will become ionized and this ionized "trail" will conduct the bolt..
It could be argued that a bunch of protons constitute an electrostatic charge. And this would be correct. But we don't see that in the "real world" so much as the "more common" contact electrification of static electricity (or triboelectric effect). The bottom line is that static electricity is the voltage created by separating charges. And because the electrons around atoms can be moved fairly easily, creating static electricity is fairly easy. The electrons and the atoms from which they came constitute the static charges, and all they want is to be reunited to neutralize that charge. (MORE)