Navigation systems

Navigation systems are the means by which people move through an information environment and understand where they are. Rosenfeld and Morville distinguish embedded navigation, built into the pages, from supplemental navigation such as site maps and indexes.

Embedded navigation

• Global — present everywhere: the main menu
• Local — within one section: a table of contents, sibling topics
• Contextual — links inside the content to related items, like the links between notes in this vault

Supplemental navigation

• Site maps and tables of contents give an overview
• Indexes (A–Z) serve people who know the term they want
• Guides and wizards walk people through a task

Navigation is built on organization

Navigation can only expose the structure that exists. A Taxonomy provides menus; Faceted classification provides filters; Metadata makes related-content links possible. Labels matter as much as structure — see Labeling systems.

Testing navigation

Tree testing evaluates a hierarchy on its own, without layout or visual cues. It isolates the question "does the structure work?" from "does the design work?" and is a direct measure of Findability.