Mechanical Energy
Mechanical energy is the sum of kinetic energy and potential energy:
EM = EP + EK mechanical energy E M is equal to the potential energy E P plus the kinetic energy E K
Thus, a transformation of kinetic energy into potential energy (or the other way around) does not alter the mechanical energy of a system.
Mechanical energy is not the same as total energy, since there are other types of energy besides kinetic and potential.