One of the simplest charge configurations in electrostatics is the elementary electric dipole consisting of two point charges of equal magnitude and opposite sign separated by a small distance. Such dipoles are useful to characterize a polarized atom or molecule in which the statistical rest position of the entire negative charge group is slightly separated from the statistical rest position of the entire positive charge group. These two charge groups, which are held together by strong interatomic forces, are electrically neutral (net charge equals zero), but can get distorted and oriented by external forces. This model is useful to characterize simple dielectric materials and is often referred to as the bound-charge model.