ok so i'm going to start out by apologizing to all the old heads here who've probably answered something like this before.

But everytime i think i get my head around it, something else crops up or someone else says something, i start to doubt what i know.

Now i understand that both EF and EF-S can both be used on crop cameras. whereas only EF can be used on full frame.

my confusion comes in when you get something like a 18-55mm EF-S lens and you put it on a crop body, do you still need to multiply it by 1.6x so in fact the focal length is about 29-88. Or because it is an EF-S lens on a crop body, it remains a "true" 18-55?

if someone can put me out of my misery and confirm this, it would be greatly appreciated!