UX Glossary · I
Information architecture
Also: IA
How content is organised, labelled and navigated, so people can find what they came for.
Information architecture is the structure underneath an interface: how things are grouped, what those groups are called, and how someone moves between them. Richard Saul Wurman popularised the term in the 1970s; Louis Rosenfeld and Peter Morville’s Information Architecture for the World Wide Web (1998) established it as a practice.
The three parts
Organisation: what belongs with what. Labelling: what each thing is called. Navigation: how you move through it. Search cuts across all three.
Labelling is consistently underrated. A perfect structure with the organisation’s internal vocabulary on it will fail, because users search with their words, not yours.
Why it is the most expensive thing to get wrong
Structure is inherited by every screen. A product organised around the company’s departments rather than the user’s tasks produces a navigation nobody can learn, and no amount of visual design repairs it. Restructuring after launch means breaking URLs, retraining users and rewriting content.
This is why IA problems are the first thing worth checking and the least visible finding in any review.
In practice
Card sorting generates a structure from users’ own groupings; tree testing validates whether a proposed structure can actually be navigated. Doing the first without the second is the common half-measure.