What is Electric Charge?

After you pass a plastic comb through your hair a few times, you will find that the comb can exert a force on individual strands of your hair. You may also observe that, once the strands of hair are attracted to the comb and come into contact with it, they may no longer be attracted to it.

If seems reasonable to conclude that the attraction between the comb and the hair is result of some physical entity being transferred from one to the other when they rub together, with the same physical entity being transferred back again to neutralize the attraction when they come into contact. This physical entity is called electric charge, and today we understand this transfer on the basis of electrons that can be removed from atoms of one object and attaché to the atoms of the other object.