16 | 16 | The most basic kind of distinction in any system of models is ontological, i.e. in the levels of abstraction of description of the real world. All models carry some kind of semantic content, but not all semantics are the same, or even of the same category. For example, some part of the SNOMED-CT1 terminology describes types of bacterial infection, sites in the body, and symptoms. An information model might specify a logical type Quantity. A content model might define the model of information collected in an ante-natal examination by a physician. These types of "information" are qualitatively different, and need to be developed and maintained separately within the overall model eco-system. FIGURE 4 illustrates these distinctions, and indicates what parts are built directly into software and databases. |