I cut and paste this from another document I had…
A Data Dictionary defines "data" by giving you details about that data element (e.g. Attribute/Field Name, Description, Data Type, Constraints, etc.)
A Vocabulary is usually a listing or grouping of words that are common a domain of context (usually without definition).
A Glossary is a more detailed Vocabulary that is tied to a specific and limited Context. Unlike a Vocabulary that only provides a list or grouping of words or terms that are common to a context, a Glossary provides the long name, short name or acronym, and a description/definition. It rarely gets into a things like synonyms and antonyms.
A Dictionary is often used interchangeably with a Glossary but is often considered to handle much more, like getting into phonetics, derivations, etc.
A Data Model is a representation of how to aggregate and interrelate Data, which is defined by a Data Dictionary. This includes but is not limited to things like Primary and Foreign Key representations, how to deal with permutations, time, history, and much more.
A Taxonomy is a categorization of "anything"… Words, Glossaries, Types, etc. Taxonomies can take on multiple forms, such as lists, hierarchies, interactive facets, etc.
A Grammar is a means of applying rules to create meaning.
A Syntax is a set of rules for structuring elements, such as words and symbols within a grammar.
A Language is the inclusion of all of the above.
An Ontology is the development of a combination of one or more of all of the above with the intent to facilitate higher order activities, such as communications, translation, learning, understanding, teaching, and making decisions.
I hope this helps.
Frank Guerino, Chairman
The International Foundation for Information Technology (IF4IT)
Food for thought and discussion:
What characteristics distinguish a Data Dictionary, Ontology, and
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