We know that the skin effect is the tendency of current to flow mainly near the surface of a conductor that happens when it is driven by a time-varying current. This situation is usually explained in case of a cylindrical conductor, like that shown in the following picture at left.
But in some situations, our conductor is so thin to be approximated as a foil (2D), for instance in case of strip lines, patches etc. Let's consider a rectangular foil as that shown in the picture at the middle. Since it's a foil, it does not have (ideally) a cross-section. Will the AC current flow uniformly along all the area of the foil, or in this case does the skin mean that AC current will flow in the edges of the foil (which are segments)?
I'd say that current will flow uniformly on all the area of the foil. But someone told me that in this case, the current on the edges is more important.
Picture taken from here.