Energy
World move on energy the bodies which passs energy exert forces
It is defined as capacity or doing work in a body is called energy
OR
work done stored in a body is called energy we are determining mechanical energy in this section

Mechanical Energy 
It is defined as the energy in a boy by virtue of its position or motion is called mechanical energy

There are two types of mechanical energy
1. Kinetic Energy
2. Potential Energy

Kinetic Energy
Energy in a body by virtue of its motion is called kinetic energy.

Electric potential Energy 
it is defined as the work done on a charge to move in the electric field is called electric potential.
Unit of electric potential is volt and 1 volt is defined as if a charge of magnitude 1c moved in a electric field and amount of work done is 1 Joule then potential or electric potential will be 1 volt. electric potential energy associated charge having energy in electric field Electric potential energy associated with position of a charge particals in electric field.

Equi Potential Energy
it is the surface on which potential or electric potential of electric field due to charge is same it mean a small charged particle charge is moved from one point to another point on equi potential surface no work done is needed.
Consider a charge particle posses electric field E same focus of same distance make Equi Potential surface.