Visual C ++ Filter Framework Concept

I am confused about how Visual Studio 2013 handles the project structure for Visual C ++ projects. It looks like Visual Studio 2013 uses some sort of "filter structure" to organize the project. But I haven't found anything about the reason for this structure. Why is this a filter structure and not a simple folder structure like in any other IDE? And why is there no documentation on this structure on MSDN? The best I could find is Project and Solution Files and the only thing that seems to say about the filter is

Projname.vcxproj.filters: Filters file. It specifies where to place the file that is added to the solution. For example, the .h file is placed in the node header files.