An electric charge (q or Q) is the quantity of unbalanced electricity in an
object (either positive or negative). It is interpreted as an excess or
deficiency of electrons. Matter that possesses a charge is influenced by and
produces electromagnetic fields.
Electrons, by convention have an elementary charge of -1. Ions are either
positively or negatively charged. The unit of measurement of the charge of an
object is the coulomb, which represents 6.24 x 1018 elementary
Magnetic field - Electric field - Electromagnetic fields (EMF) - Ion(s)