The ZOO Metasystem: A Direct-Manipulation Interface to Object-Oriented Knowledge Bases.

Transparency and adaptability are important criteria for the usability of computer systems. It is not easy to fulfill these criteria in ill-structured domains by using traditional software concepts. The object-oriented approach, however, allows the construction of metasystems which enable the user to understand and manipulate the underlying conceptual schemata of an application system. ZOO is a metasystem for the application expert. ZOO visualizes the contents of an object-oriented knowledge base in a graphic, spatial representation as a net of icons. ZOO allows its user to inspect, manipulate, create and delete the components of a knowledge base through direct manipulation of graphic objects. [ABSTRACT FROM AUTHOR]