Which way do case fan screws go?

[Hork]

Newbie question here...

Which way do the case fan screws go?

For the rear fan... Do the screws go from the outside of the case through the metal of the case and into the fan inside the case, or do they go through the fan inside the case and the into the metal of the case?

 

[screw3d]

It is possible to do both ways, but screwing it from outside-in is much more convenient and looks much better.

If you do it the other way round, won't the screws jut out and catch some skin?