The Accidental Taxonomist: “Is a taxonomy the same as a classification scheme or system? Or, to put it another way, is a classification system, such as the Dewey Decimal System, a kind of taxonomy? Both of these kinds of knowledge organization systems have the feature of arranging topical terms in a hierarchy of multiple levels, without having related-term relationships or necessarily synonyms/nonpreferred terms, which are features of thesauri. So, it appears as if the only difference is that classification systems have some kind of notation or alphanumeric code associated with each term, and taxonomies do not. The differences, however, are greater than that…”