The BDF file is used only by the BrowserHawk Editor. Therefore, if you wish to view or customize the browser definitions you will be opening the maindefs.bdf file. If you make any changes to the BDF in the BH Editor it automatically generates a new, matching BDD file with your changes.

The BDD file is used only by the BrowserHawk component. Therefore, when you create an instance of either of these components from your scripts or programs, it is the data in the BDD file that is read and used by the component.

When an updated BDF file is downloaded (either manually through the BH Editor or automatically through the BDF Service), it automatically downloads and installs the matching BDD file for use by the component.