When .NET 1.0 came out, it was originally supported on Windows 98 SE. Therefore, I assume that given the assembly in which you found it, it was originally available for switching between Win9x Win Forms and WinNT (2000, XP, Vista, etc.) Win Forms.
Since Win9x and WinNT used different messaging protocols. If you are new to Windows Messaging, this is a way for Win Forms to interact with the OS for things like drawing, keyboard events, mouse events, and everything else.
Nick berardi
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