Modifying the library containing "labels"

I want to re开发者_Python百科place the Windows DLL that contains the label object. At first, I thought just each of the installs of the .NET Framework would contain it, but some applications don't utilize the .NET Framework and still have labels. I was wondering, what DLLs contain the label object? Is there only one (like, at the top that they all reference)? Do they all have it?