Workspace tab
Displays a hierarchy of the objects in the active workspace. A workspace is the subset of the active model database you specified when you started your design session. See What is a workspace? and Define a workspace.
You can select a parent that is not an active object type in the locate filters, such as another system or part. Because the software filters the parent system list, only valid parent systems are available in the Select Parent System dialog. Invalid parent systems appear dimmed.
Model tab
Displays a hierarchy of all the objects in the active model, including those that are not part of your workspace.
You can select a parent that is not an active object type in the locate filters, such as another system or part. Because the software filters the parent system list, only valid parent systems are available in the Select Parent System dialog box. Invalid parent systems appear dimmed.
Expand to Current Parent
Expands the hierarchy to display and highlight the current parent system.