The distinction between information architecture and usability may seem like semantics, but there are significant differences between the two disciplines.
Though they are often discussed interchangeably, and practitioners are often well-versed in both, information architecture and usability differ in their scope and areas of focus.
The difference between information architecture and usability is important to understand because information architecture is more than just understanding what users want and need. A usability-only approach to information architecture is only one piece of the puzzle.
Information architecture problems often account for a large percentage of usability problems, but there are many other things unrelated to information architecture that have an impact on usability.
Usability encompasses two related concepts:
- Usability is an attribute of the quality of a system: "we need to create a usable intranet".
- Usability is a process or set of techniques used during a design and development project: "we need to include usability activities in this project".
In both cases usability is a broader concept, whereas information architecture is far more specific.
Usability is a detailed subject, taking into account things like font size, colors, visual proximity, usage context, search, error messages, navigation, form design, and labeling. Of these, only a few are true information architecture issues. Navigation, labeling, site architecture and search results all have an impact on the usability of a site, but they are not the only things that affect usability.
An effective information architecture is one of a number of attributes of a usable system. Other factors involving the usability of a system include:
- visual design
- interaction design
- content writing
The process for creating an effective information architecture is a sub-set of the usability activities involved in a project. Although weighted to the beginning of the project, usability activities should continue throughout a project and evaluate issues beyond simply the information architecture.
In terms of great usability information architecture, it is the information architecture that makes it easy for users to find desired information or functionality. On a website, the information architecture can also add important context to the current page (for example when a user begins their visit deep within the website, having come directly from a search engine).
A "bricks and mortar" architect must balance the demands of aesthetics, structural integrity, heating, lighting, water supply and drainage when creating building blueprints. Similarly, an information architect must create navigation schemes for web sites, content management systems, etc. that are at once concise, descriptive, mutually-exclusive, and intuitive. Both types of architects seek to create spaces for humans that are safe, predictable, enjoyable, and inspiring.
Usable navigation systems should:
- Be easy to learn.
- Be consistent throughout the web site, CMS, etc.
- Provide feedback, such as the use of breadcrumbs to indicate how to navigate back to where the user started.
- Use the minimum number of clicks to arrive at the next destination.
- Use clear and intuitive labels, based on the user’s perspective and terminology.
- Support user tasks.
- Have each link distinct from other links.
- Group navigation into logical units.
- Avoid making the user scroll to get to important navigation or submit buttons.
- Not disable the browser’s back button.
Steps to develop an intuitive information architecture:
1. Find out what the mission or purpose of the website is: why will people come to your site?
2. Determine the immediate and long-range goals of the site: are they different?
3. Pinpoint the intended audiences and conduct a requirements analysis for each group.
4. Collect site content and develop a content inventory.
5. Determine the website’s organizational structure, which can include:
- narrow and deep
- broad and shallow
6. Create an outline of the site, which can include:
- Content Inventory: a hierarchical view of the site content, typically in a spreadsheet format, which briefly describes the content that should appear on each page and indicates where pages belong in terms of global and local navigation.
- Site Maps: visual diagrams that reflect site navigation and main content areas. They are usually constructed to look like flowcharts and show how users will navigate from one section to another. Other formats may also indicate the relationships between pages on the site.
7. Create a visual blueprint of the site, which can include:
- Wireframes: rough illustrations of page content and structure, which may also indicate how users will interact with the website. These diagrams get handed off to a visual designer, who will establish page layout and visual design. Wireframes are useful for communicating early design ideas and inform the designer and the client of exactly what information, links, content, promotional space, and navigation will be on every page of the site. Wireframes may illustrate design priorities in cases where various types of information appear to be competing.
8. Define the navigation systems:
- Global navigation: Global navigation is the primary means of navigation through a website. Global navigation links appear on every page of the site, typically as a menu located at the top or side of each web page.
- Local navigation: Local links may appear as text links within the content of a page or as a submenu for a section of the website. Local navigation generally appears in the left-hand margin of a web page and sometimes is placed below the global navigation.
9. Conduct user research. Once you have a draft navigation structure, conduct appropriate usability research to collect feedback from the target audience. Methods may include: card sorting, cognitive walkthroughs, contextual task analyses, and usability testing.