It indicates that this is a control panel. The orientation is yes, random. The rest of the icon personalizes it. It was same for other file types: the general

It indicates that this is a control panel. The orientation is yes, random. The rest of the icon personalizes it. It was same for other file types: the general shape plus some personalization. Documents were taller rectangles resembling a sheet of paper with a folder corner, templates were like two sheets on top of each other, programs were squares rotated to 45 degrees, often with a hand, folders were wider rectangles with a tab, clippings were wider rectangles with a serrated edge.