Mouth to lung vs Lung inhale

[Jonah]

What is mouth to lung inhale? when i vape i breath like im breathing air but sometimes it is difficult to do this when i use sub ohm rda builds because i cough, i believe this method is lung inhale? How do you perform a mouth to lung inhale and why would you over a lung inhale?
Thanks

 

[martinelias]

Mouth to lung you pull with your mouth then suck it in like you would a cigarette. Lung inhale you pull from within, like you would with other smoking stuff that arent cigarettes.