# Complex attributes A complex attribute is an attribute that consists of two or more simple attributes that go together to convey some composite information about a feature. They only exist within the GML format. Further information on complex attributes in OS MasterMap Topography Layer is detailed in the following sub-pages.

UML for the Change History Type Data Type in OS MasterMap Topography Layer.

UMLs for the Height Above Datum Type and Height Above Ground Level Type Data Types in OS MasterMap Topography Layer. — UML diagrams for the Height Above Datum Type and Height Above Ground Level Type Data Types in OS MasterMap Topography Layer.

UML for the Text Rendering Type Data Type in OS MasterMap Topography Layer.

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