ATG Repository supports the inheritance of Objects through concepts of super-type and sub-type. Sub-type inherits all the properties of Super-type. Super-type can have multiple sub-types.Following example shows "Library content" can be either "Book" or "Video CD". "Library content" is Super-type and "Book" and "Video CD" are sub-types.
Object Model
<!-- Library content--><item-descriptor name="libraryContent" sub-type-property="type"> ...