A user interface plug-in module adds one or more extensions to the vSphere Client user interface layer.

Extensions to the user interface layer can include either global views or views that are specific to a given object. The latter are called context-specific views. When you create a data view extension, you must also create the actual GUI objects in HTML and package them in the plug-in module. These GUI objects rely on data from the vSphere Client service layers. You can use the libraries included with the vSphere Client SDK to enable communication between your GUI objects and the service layer or if you create an HTML plug-in, you can use a library of your choice.

Other user interface extensions can include new workspaces for custom objects, shortcuts added to the object navigator, new relations between vSphere objects, and new actions associated with vSphere objects.