Hi Stephanie,

Electric potential energy is what you know of energy from other units. It cannot be destroyed but can be converted.
The equation is kq1q2/r. This means it is proportional to the magnitude of q2 in an electric field created by charge q1. Remember, point charges create electric fields.

On the other hand, voltage is kq1/r. This means voltage is fixed for a certain point in the electric field created by q1. This means it doesn't matter what magnitude the charge is, all charges will experience the same electric potential. The comparison is basically all the charges at that point in the field are like multiple masses all having the same velocity. They have different masses though, and as a result, have different potential energies.

Hope this helps clarify the difference.

Simon