The paper provides a classification and typology of various configurat
ions which make up the definition of an Information System (IS), It is
based on five basic building blocks: source, data, prediction, value,
and action. Using those building blocks, it is possible to formally o
utline many configurations including data base management systems (DEM
S), decision support systems (DSS), expert systems (ES), and autonomou
s intelligent machines (AM), This paper formally defines the building
blocks, functions and operators of systems that fall into the class of
information system, The result is a cohesive construct of transformat
ions for IS through which a variety of new configurations and systems
are enumerated and explained. Such model, may make it possible to asse
mble an information system from ''of the shelf'' components rather tha
n constructing it as done today.