(N/A) $1$. Energy Gap: The energy gap is the difference in energy between the top of the valence band and the bottom of the conduction band in a solid. It represents the minimum energy required for an electron to jump from the valence band to the conduction band to participate in electrical conduction.
$2$. Forbidden Gap: The forbidden gap is the energy range between the valence band and the conduction band where no electron states exist. Electrons cannot occupy any energy levels within this region. In insulators,this gap is large,while in semiconductors,it is relatively small,and in conductors,it is non-existent (the bands overlap).