What is Step voltage?

 I m heard, that on thunder time is happening step voltage, does it dangerous for us? And ,  what is it?

 In thunder hit in tree, thunder tap or support for elector transfer is elector current enters in earth and spreading in ground in all sides till a few ten metres. And same happening in fallen on earth elector tape, as by voltage. A most resistance having soils layers, lied close to current entered in earth, thus here is having high voltage, and by a method for removing this point for resistance a transferring current is decreasing, and voltage lowering. As a think about, that discharge for thunder is in tree hit, close where stayed person, and elector current of thunder entering in earth, spreading in her, it happens under human s legs, if legs separated, thus current enter in one leg and transfer through body, leave through earth through others. And here human staying under step voltage. A thus, step voltage is voltage for current, displaying between points on the earth top, separated by distance of  75 cm, by a middle length for step. A most dangerous is step voltage where is human staying on distance on 4 metres  from a place circuit a current in earth. And against affecting of step voltage a need all gadgets of earth grounding put, where are not staying peoples. As in villages, thunder taps to ground on a not close for 4 metres from houses walls and protect theirs. And,  on the thunder time keep far from a support of power transmission, not stay close to high trees, on an opened area. It's  need, that to any close secreting on the surface an item as tree, thunder tap, mast, power transmissions are on the thunder time creating conditions, where thunder directing to this item, and damaging all in radius on ten metres. And in damage by thunder for patient add artificial breath, and closed heart massage.