Electromagnetism ... the second step on the road to unification

first: Newton unified planetary & terrestrial gravity

like the force the floor exerts on your feet,
       most everyday forces due to electromagnetic
       forces resist displacement of atoms
       from equilibrium position  

  +   

Maxwell: second unification of forces - electricity
       and magnetism
electrical charge (positive/negative) and
       magnetism (north/south) are different aspects
       of the same force -- electomagnetism
Oppositely charged objects, such as a proton
       and electron, attract one another,
       particles with the same charge repel each other