A property possessed by some elementary particles causing them to exert forces of attraction or repulsion on each other. The types of force exerted by charged particles are differentiated by the terms negative and positive, the natural unit of negative charge being possessed by the electron. The proton has an equal amount of positive charge. A charged body contains an excess or lack of electrons with respect to its proton content.

Two electric charges, when close to each other, exert a force on each other. This force is given by Coulomb’s law and can be explained in terms of the electric field surrounding the charges. If a charge, Q, is placed in an electric field E it experiences a force QE.