File created by Microsoft Visual Studio, A Mac SDK; contains a pre-parsed binary representation of a .XAML file produced by the XamlBinaryWriter class; intended to be write-once. By producing the XBF file, loading and parsing performance becomes better, especially when loading XAML files that define large resources. The XBF file will appear as App.xbf in the subdirectory of its related application. NOTE: If you compile your XAML file into the XBF format you should still maintain the XAML in its text state so that it remains human-readable. Common XBF Filenames: App.xbf - Default name given to the binary representation of the XAML file of each app.