A Vocabulary is represented as a hierarchical tree:

The top level—the root node of the tree—is the Vocabulary Name. Its icon is an open book icon. In this example, Cargo is the Vocabulary Name:

One level under the Vocabulary name are its entities. Entities have a golden box icon. Each entity name must be unique in the Vocabulary.

Indented under each entity are its attributes. Each attribute has a name, a data type, and a few other properties. Each attribute has a golden box icon with a green bar.

Finally, associations are at the same hierarchical level as attributes. The associated entity is displayed in parentheses. The association icon changes based on the type of association. Because the Cargo entity has a many-to-one relationship with the FlightPlan entity, the icon is multiple bars converging into a single horizontal bar. The FlightPlan to Cargo association shows a reverse of the icon—a single bar diverging into multiple bars.