Tesla Coil

Last night when i was watching the television i came across a program about Tesla coils. They charge by touching. While the generator below the coil generates huge amounts of electricity the charge is stored in a large dome structure at the top of the coil. Its like a large van de Graff generator, but it gathers huge amounts of electricity which is expelled out of the top of the dome structure. This is what i was watching and this deals directly with charging by touch. From generator to dome.