For any type that has a non-trivial inheritance hierarchy, the synopsis is followed by a “Hierarchy” section. This section lists all of the supertype of the type, as well as any interfaces implemented by those supertypes. It will also list any interfaces implemented by an interface. In the hierarchy listing, arrows indicate supertype to subtype relationships, while the interfaces implemented by a type follow the type name in parentheses. For example, the following hierarchy indicates that System.IO.Stream implements IDisposable and extends MarshalByRefObject, which itself extends Object:

System.Object → System.MarshalByRefObject → System.IO.Stream(System.IDisposable)

If a type has subtypes, the “Hierarchy” section is followed by a “Subtypes” section that lists those subtypes. If an interface has implementations, the “Hierarchy” section is followed by an “Implementations” section that lists those implementations. While the “Hierarchy” section shows ancestors of the type, the “Subtypes” or “Implementations” section shows descendants.