Linking models is primarily intended for linking separate buildings, such as those that compose a campus.
You can link Revit LT models to other Revit LT models. You can also link Revit models to Revit LT models.
For example, the following site plan shows 4 building models linked to one model.
When you link a model into a project, Revit LT opens the linked model and keeps it in memory. The more links a project contains, the longer it can take to open.
Linked models are listed in the Revit Links branch of the Project Browser.