Well I am not sure where to post this. But, anyway, I am finding 'potential' to be rather difficult. Afterall what is this potential? it comes popping out in different forms such as in potential energy ,potential difference ,electric potential etc. I also know ,for example, that electric potential is a scalar way of describing the electric field; a system always contains some potential energy, BUT I don't see any need to do this. Electric field can always be described by vectors, then where is the need for potential? Potential energy is also related in the formulation of langrangian which is yet another way of describing classical physics. Please explain to me that afterall why this potential was invented?