When you define an information model in Microsoft® Repository, you define classes of objects, types of relationships that can exist between objects, and various properties that are attached to these object classes and relationship types. The object classes that you define in your information model are represented by instances of the ClassDef class.
To insert a new class definition into an information model, use the ReposTypeLib class.
Use the ClassDef class to complete the definition of a new Repository class. You can define new interfaces and attach them to the class definition. You can also attach existing interfaces to the class definition.
| Interface | Description |
| IAnnotationalProps | Gets and sets annotational properties. |
| IClassDef | Manages class definitions. |
| IRepositoryDispatch | Provides enhanced dispatch support. |
| IRepositoryItem | Manages Repository objects and relationships. |
| IRepositoryObject | Retrieves Repository object identifiers. |
| IRepositoryObjectStorage | Creates and loads Repository objects. |
| IReposTypeInfo | Contains the collection of definition objects that are associated with an information model's Repository type library. |