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Electric force holds matter together. It exists between all charged particles. 
The smallest charged particles are the protons and electrons that exist within atoms. They represent the two types of electric charge contained in an atom. 
Protons have a positive charge, and electrons have a negative charge.
Particles with opposite charges exert an attractive force on one another. Particles with like charges repel, or exert a repulsive force on, one another.
Many atoms have an equal number of protons and electrons.  In these atoms, the positively  and negatively charged particles cancel each other out, so the atom has no charge, or is neutral.
In an atom, protons remain within the atom’s center, or nucleus. Electrons constantly move around the nucleus in orbits.
Because the electrons move much more freely, it is somewhat easy for them to move from one atom to another. This creates an imbalance of charge within the atom. The atom that loses the electron becomes positively charged. The atom that gains the electron becomes negatively charged. Charged atoms are called ions.