In resonant vibrations of a body, the frequency of external force applied on the body is equal to its natural frequency. If on increasing and decreasing the frequency of external force from the natural frequency by a factor, the amplitude of vibrations reduces very much. In this case sharp resonance will take place. But if it reduces by a small factor then flat resonance will take place. The sharp and flat resonance will depend on damping present in the body executing resonant vibrations. Less the damping, greater will be the sharpness.