The art and science of structuring information (knowledge) to support findability and usability.
Allows for intuitive navigation and quick access to relevant content, supports interaction with content (usability), and makes the body of content both maintainable and extensible.
Information Architecture (IA) is both a process and a product. The process involves analyzing a body of content—a domain—to understand its components, the relationships among them, and their behavior; identifying the organizing principles; and designing a conceptual model that captures the underlying structure. The product is the conceptual model.
A typical IA model will feature one or more hierarchical structures (shown diagrammatically as inverted trees, with leaves at the bottom) with a secondary network structure. Hierarchies arise from the nesting of categories and sub-categories. In the digital world, a single piece of information (a leaf on the tree) can be part of more than one hierarchy, using a faceted categorization scheme. Relationships between components within or across hierarchies are allowed. This cross-linking (via hyperlinks) results in a secondary network structure.
Good IA results in a body of content that is:
In addition, clear IA informs the graphical design process, contributing to a coherent look and feel across the content domain.
The Discipline of Organizing by Robert Glushko
Information Architecture for the World Wide Web by Peter Morville and Louis Rosenfeld