User View: a selection or recombination of attributes of one or more objects according to the needs of a specific user (role). Comprises additional constraints, like acessability and changeability of attributes and objects. Comparable to logical views in relational databases, but fully object oriented.

Surface View: the surface of a respective object, not the surface of a concrete technical device, like a monitor. Specifically, the application surface, i.e. the whole user interface, consists of all those: the logical object surface on top of the user view, plus the media view.

Characterisitcs:

• logical surface of object(s)

• not mapped to any media (presentation, picture)

• frontend (media) independent

• not specific to backend (business logic)

• domain logical usability

• functional complete

• equipped with meta data and human readable information

• generic (like reflection)

• dynamic (changeable at runtime, adaptable)

• standard software component

Media View: mapping of surface view to a specific frontend, like desktop, HTML, WML, text, voice, 3D and multimodal combinations.