A class implements one or more interfaces. A Repository object is an instance of a class, and therefore provides one or more interfaces, as defined by the class to which it conforms. The Repository object is encapsulated and is only accessible through its interfaces. Each interface is composed of properties, methods, and collections.
By default, the Repository Browser displays interfaces in the Repository hierarchy. If you find the visualization of interfaces distracting, use the Repository Filter dialog to turn off the display of Repository interfaces.