Icon replacement. Which file usually?

[h1r0ll3r]

I'm slowly getting into the process of swapping out my icons now and had a general question about this.

When replacing icons, I've noticed that there are usually two icons associated for each icon, basically. For example, I'll see

IconDarkeningOverlay.png
IconDarkeningOverlay@2x.png

In terms of replacing the springboard icon, would I be correct in assuming that I'd need to replace the "@2x" for each icon?

If that's the case, then what purpose does the other png serve?

Thanks.

 

[sidewinder]

The @2x.png files are for devices with the Retina display. The other file is for the those devices with the regular display.

S-