Taxonomy is a practice in which things are arranged and classified to provide order. A classic example of taxonomy is scientific or alpha taxonomy, the system used to classify all living organisms. As scientific taxonomy demonstrates, the process of classifying things serves a number of functions, and it can be extremely beneficial to a greater understanding of the objects, ideas, or organisms being classified.
This term comes from the Greek, and it literally means “arrangement method.” There are a number of ways to arrange things, ranging from codified taxonomical systems which are widely recognized, like the Dewey Decimal System, to personal systems which people use to organize things in a way which makes sense to them. For example, many websites break their contents down into categories to make it easy for users to find specific topics of interest.
Humans appear to have a natural tendency to want to order and name things, and from a very young age, people are engaging in taxonomy, even if they aren't fully aware of it. For example, children learn that bananas are a type of fruit, but that not all fruits are bananas. This provides them with a general category, “fruit,” and a subtype, “banana.” Over time, they may add additional categories to the hierarchy, like “tropical fruit,” or “unripe banana.” In the process of ordering things and putting names to them, the child learns about the relationships between various objects in the taxonomy, and gains a greater understanding of the world at large.
Almost any collection of objects can be subjected to taxonomy, and often is, from libraries, which are arranged using cataloging systems to make books easier to find, to personal collections of model aircraft, which may be arranged by manufacturer, era, style, and so forth. In all cases, the organization of the objects is designed to bring order to the collection, and to allow people to see how objects are related.
Taxonomy also allows people to define and name things. In the banana example above, for example, a child learns that something with a distinctive yellow color and curved shape can be called a banana or a fruit, but that something which is round and red is not a banana, although it may be a fruit. Because the taxonomy for fruits is standardized, a child also knows that when he or she asks someone else for a banana, a banana will be produced, not an orange.