| interface  | IFragment | A model object that represents the content of the fragment.xml
 file. | 
| interface  | IPlugin | A model object that represents the content of the plugin.xml
 file. | 
| interface  | IPluginBase | A model object that represents the content of a plug-in or
 fragment manifest. | 
| interface  | IPluginExtension | Classes that implement this interface model the extension
 element found in the plug-in or fragment manifest. | 
| interface  | IPluginExtensionPoint | Classes that implement this interface model an extension point
 element specified in the plug-in manifest. | 
| interface  | IPluginImport | Objects that implement this interface represent references
 to required plug-ins. | 
| interface  | IPluginReference | Objects that implement this interface represent references of
 plug-ins. |