Zapping is one term for equipment used to get Frequencies to the body. As far as I know, all Zappers use a constant frequency (or have a setting for several frequencies) and deliver this for a time.
Spooky is a different piece of equipment that may be used to get frequencies into the body. It is much more powerful than a Zapper due to several reasons:
1) It has a higher amplitude capability than a Zapper.
2) It is controlled through a computer software, so it has far more functionality and control than the Zapper.
3) Spooky has 3 different modes to get the frequencies to the body. Contact (like Zapper), Remote(via personal DNA), and Plasma.
Frequency is the rate of change of the waveform from high voltage to low voltage between the levels set. The effective killing or deactivating frequency varies for different pathogens, so it is important to be able to use different frequencies depending on what the user desires to accomplish by use of frequency.