An Abstraction is a Dependency relationship that relates two elements or sets of elements that represent the same concept at different levels of abstraction or from different viewpoints.
An Abstraction can be specified by changing its property values in the Abstraction Specification window. Each property is described in the description area in the Specification window.
You may see between which elements Abstraction is drawn in the Abstraction dialog, Source and Target boxes.
Set the Abstraction symbol properties in the Symbol Properties dialog.
