Standard Edge Doors are the American "traditional" style door type. The interior door panel is flush with the door fame and have all concealed door hinges.
European Edge interior doors are the standard European appearance, known as "rabbeted" edge. The door panel overlaps the frame, on the "room side", while the "hallway appearance" is the same as a "Standard Edge". The European Edge interior doors allow for less light and sound however, do not allow for a magnetic mortise.