Mac OS X determines what area to scroll by the mouse position. Windows does this by what application is active.
So I thought anyway. If Notepad++ is the active application in Windows, I can scroll underlying applications by placing the mouse pointer on them. But this seems like the only application with this behaviour. Windows Explorer (Win7) doesn't even allow scrolling in the side pane if the pane is not active.
My question is, can this be controlled by developers, and why is Windows behaving like this? I am not about to make a Windows application, but as a developer this makes me curious (and annoyed).