At projectProperties->linker->Additional Dependencies i have following line:
kernel32.lib;user32.lib;gdi32.lib;winspool.lib;comdlg32.lib;advapi32.lib;shell32.lib
Visual Studio lets you use Property Sheets. Your project can have various configurations, which can have properties from any/all of your Property Sheets, plus locally defined properties.
For example, on one recent project, I created the following property sheets: 1) common, 2) 32 bit, 3) 64 bit, 4) Debug, 5) Release.
A given configuration (e.g., 32-bit English Release build) would have a combination of those: 1 + 2 + 5 + property-specific "English" definition.
The macro you're seeing is used for "do I use properties from the property sheet plus additional properties" or "do I override the properties entirely and ignore the property sheets."
It's kind of a trick to set these up correct the first time, but it really simplifies maintaining multiple project settings.