Taxonomists are often asked about the work they do. For those outside the world of information science and management, it can be hard to get their head around classification and the science of taxonomy. To put it at its simplest — taxonomy is a knowledge organization system, usually for a specific subject area.

This interesting video from The Brain Scoop classifies candy using the science of taxonomy. It is a short lighthearted look at a serious science being applied in a not-so-serious way.

The video points out you can group all red candy together and then sort them by chocolate, fruit flavor etc, however, you wouldn’t group all red animals together because for instance, red foxes and red bats do not share a common ancestor.

As fun as it is to watch serious scientists apply their knowledge to sorting Skittles, it does represent the importance of having the right people do the job.

There are many approaches to the building of a thesaurus or taxonomy. No absolutely right or absolutely wrong methods exist, but there are some that are not as efficient as others such as grouping red animals together. They may share the same color attribute, but that might end up being the only thing that they share. Consistency and clarity of meaning are vital benefits of taxonomies; they give taxonomies the power to do what they do for knowledge management.

With content management system vendors providing taxonomy functionality, users have unfortunately become tempted to consolidate and eliminate a very worthy part of their document management process.

Subject matter experts need to be used in creation of a good taxonomy – without their knowledge you will miss the important detailed knowledge of the users. Taxonomies aren’t complicated, or they don’t have to be. They are a simple means of organizing information.

So then a thesaurus and taxonomy are the same things, right?


A taxonomy is solely the hierarchy, while a thesaurus brings some control to the synonyms, the hierarchies, and the related terms.

A thesaurus is also a controlled vocabulary. Since many thesauri are hierarchical, they may be referred to as taxonomies. However, unlike a simple taxonomy, a thesaurus does have synonyms, related terms and scope notes. A thesaurus focuses on concepts. It doesn’t focus on the information object itself. Rather than outlining those information objects, as a taxonomy might, it is giving you a guide to those information objects. You could take the red candy and sort it into chocolate flavored and fruit flavored. That would be the taxonomy. To turn it into a thesaurus then, you would add specific things under chocolate such as M&M’s, Malt Balls, and Milk Duds. You could even expand the M&M branch to describe the regular ones, peanut, dark chocolate, peanut butter etc. and add the colors, or leave a note saying “all colors”. It really is limitless in what you can do.

Despite these differences, taxonomy and thesaurus often are used interchangeably. Many times users start with categorization, and taxonomy grow into a thesaurus as they add related terms over the years and figure out the relationships. New terms are discovered, new words are formed, and new meanings are discovered.

Melody K. Smith

Data Harmony is an award-winning semantic suite that leverages explainable AI.

Sponsored by Access Innovations, the world leader in thesaurus, ontology, and taxonomy creation and metadata application.