The foreground window is the window at the top of the Z order.
It is the window that the user is working with.
In a preemptive multitasking environment,
you should generally let the user control which window is the foreground window.
Windows NT 5.0 and later: An application cannot force a window to the
foreground while the user is working with another window. Instead,
SetForegroundWindow will activate the window (see SetActiveWindow) and
call theFlashWindowEx function to notify the user.