Category (noun.)

Definition: A class or division of people or things regarded as having particular shared characteristics.

Also referenced as: Categories (noun) Categorization (noun)

Related to: Arrange, Associated, Classification, Connection, Define, Label, List, Sort, Structure, Taxonomy


Chapter 1: Identify the Mess | Page 13

Information architecture is all around you.

Information architecture is the way that we arrange the parts of something to make it understandable.

Here are some examples of Information architecture:

  • Alphabetical cross-referencing systems used in a dictionary or encyclopedia
  • Links in website navigation
  • Sections, labels, and names of things on a restaurant menu
  • Categories, labels and tasks used in a software program or application
  • The signs that direct travelers in an airport

We rely on Information architecture to help us make sense of the world around us.

Chapter 6: Play with Structure | Page 130

Ambiguity costs clarity; exactitude costs flexibility.

The more ambiguous you are, the more likely it is that people will have trouble using your taxonomy to find and classify things.

For every ambiguous rule of classification you use or label you hide behind, you’ll have to communicate your intent that much more clearly.

For example, what if I had organized the lexicon in the back of this book by chapter, instead of alphabetically? This might be an interesting way of arranging things, but it would need to be explained, so you could find a term.

The more exact your taxonomy becomes, the less flexible it is. This isn’t always bad, but it can be. If you introduce something that doesn’t fit into a category things can get confusing.

Because there are many words for the same thing, exact classifications can slow us down. For example, I recently tried to buy some zucchini at a grocery store. But it wasn’t until the clerk in training found the code for “Squash, Green” that she could ring me up.

Chapter 6: Play with Structure | Page 137

Taxonomies can be hierarchical or heterarchical.

When taxonomies are arranged hierarchically, it means that successive categories, ranks, grades, or interrelated levels are being used. In a hierarchy, a user would have to select a labeled grouping to find things within it. A hierarchy of movies might look like this:

- Comedies

  • Romantic comedies
  • Classic comedies
  • Slap-stick comedies

Hierarchies tend to follow two patterns. First, a broad and shallow hierarchy gives the user more choices up front so they can get to everything in a few steps. As an example, in a grocery store, you choose an aisle, and each aisle has certain arrangement of products, but that’s as deep as you can go.

A narrow and deep hierarchy gives the user fewer choices at once. On a large website, like usa.gov, a few high level options point users to more specific items with each click.

When individual pieces exist on one level without further categorization, the taxonomy is heterarchical. For example, each lettered box in the arrangement in this illustration is heterarchical.

Chapter 6: Play with Structure | Page 139

Taxonomies can be sequential.

Sequence is the order in which something is experienced. Some sequences happen in a logical order, where the steps are outlined ahead of time.

Other sequences are more complex with alternative paths and variations based on the circumstances, preferences, or choices of the user or the system.

These are all examples of sequences:

  • A software installation wizard
  • New patient sign-up forms
  • A refund process at a retail store
  • A job application
  • A recipe
  • A fiction book
  • The checkout process on a website

Like any taxonomy, the categories and labels you choose affect how clear a sequence is to use.