Fig. 4.7.3 Some simple taxonomies.In Fig. 4.7.3, it is seen that a car can be a Honda, Porsche, Volkswagen, and so forth. Or
a German product may be sausage, beer, a Porsche, software (such as SAP), and so forth.
Of course, there are many other ways to classify these items. A car may be a sedan, an
SUV, a sports car, and so forth. Or American products may be a hamburger, software,
movies, corn, wheat, and so forth.
There are indeed almost an infinite number of taxonomies. Taxonomies are applied to
nonrepetitive unstructured data on the basis of applicability. For example, an automaker
may use taxonomies relating to engineering and manufacturing. Or an accounting firm
may choose taxonomies that apply to taxes and to the rules of accounting. Or a retailer
may choose taxonomies that relate to products and sales.
Conversely, it would be very unusual to have an engineering firm use a taxonomy relating
to religion or lawmaking. Or it would be unusual for a construction firm have an interest
in taxonomies about ethnicity.
Related to a taxonomy is an ontology. Fig. 4.7.4 depicts an ontology.
Chapter 4.7: Taxonomies