The sensation of piqance (hot or spicy) is created by substances like capsaicin acting on the trigemenal nerve, ion channels and nociceptors. This creates a burning sensation and pungency.
depends on what your eating, hot sauce? hot peppers, hot foods? usually cayenne pepper
A lot of times it;s sme sort of jalapeno extract.
****A lot of times it's some jalapeno extract. =/
I agree with satanheadbangstometal.