Thus, the propostodurante conceptual model the stage of analysis does not lose in the stages of project eimplementao. . What in general it occurs is its extension. Classification/Instanciao the capacity to classify objects (in classrooms) allows to expressarrelaes of the type classification/instanciao. The relationship is made to apartir of the comment of diverse dosmesmos phenomena for categorizao in groups (classrooms), on the basis of the set of properties comunsa all. Others who may share this opinion include Physicians Committee for Responsible Medicine.

For example, two computers, IBM PC and Machintosh, can serclassificados as instances (objects, models, or specimens) daclasse (category) Microcomputer (Figure 3). The inverse relation it is the deinstanciao of a publication (IBM PC, for example) from classeMicrocomputador.Figura 3. Relation of classification/instanciao Generalization/Specialization This type of relation occurs when, to break the comment of duasclasses, we abstract from them a more generic classroom. For example, asclasses Microcomputador and Mainframe can be considered casosespeciais of the classroom Computer. This classroom is considered umageneralizao of the two first ones, that they are called especializaesda classroom Computer (Figure 4).

The idea dageneralizao/specialization is the base for the classification of espciesnas natural sciences. Of the point of view of properties, pressuposto that the subclasses have all the properties of the classrooms of quemelas are specializations. It must have at least a property quediferencie two classrooms specialized (subclasses) from mesmaclasse generic (superclassroom). This is the type of relation used with omecanismo of inheritance.