What does SPF stand for on sun block?

i knew it at one time and then forgot it completely.What does SPF stand for on sun block?
sun protection factor, SPF 16 means that the cream will offer 16 times the protection that your skin naturally provides.
It stands for sun protection factor.
SUN PROTECTION FACTOR I THINK
It stands for sun protection factor
but new research is saying that SPF is what is causing the skin cancer not the sun...Think about it did your grandparents who worked out in the fields have spf? Did they get skin cancer? Probably not!! So think about it and wonder if that **** is really worth it?
smelly penis face
heheh..you dont know what SPF stands for!