Dipole moment is denoted by
. Where gives the value of the strength of the Electric dipole. Dipole moment is a vector quantity.
I.e. 
or
The direction of dipole moment is towards positive charge from negative charge. S.I. unit of Dipole moment is coulomb-meter(C-meter). If the distance between the charges becomes smaller but the charge q becomes larger. The product will be shown as:
The above equation formed is the equation of an Ideal Dipole. Now the question arises what is an ideal dipole?
An ideal dipole is a smallest dipole having a negligible size.