Extending the Taxonomy
In addition to inverting the hierarchy, we found practical value in adding two levels of abstraction: Applications and Principles. Applications provide a place to document overall product and business information to give context about how and why the pages within an application are organized. Principles were added below the Atoms as a repository for our generalized interaction patterns; patterns such as how and why to use animations or the proper way to truncate text. These are the foundational patterns that designers should be aware of and follow when creating new patterns, but don’t by themselves have any source code. Both Applications and Principles will be discussed in more detail later.