<P> A data model (or datamodel) is an abstract model that organizes elements of data and standardizes how they relate to one another and to properties of the real world entities . For instance, a data model may specify that the data element representing a car be composed of a number of other elements which, in turn, represent the color and size of the car and define its owner . </P> <P> The term data model is used in two distinct but closely related senses . Sometimes it refers to an abstract formalization of the objects and relationships found in a particular application domain, for example the customers, products, and orders found in a manufacturing organization . At other times it refers to a set of concepts used in defining such formalizations: for example concepts such as entities, attributes, relations, or tables . So the "data model" of a banking application may be defined using the entity - relationship "data model". This article uses the term in both senses . </P>

When can models be used to collect data