MET:Information Architecture

From UBC Wiki

Original Article Started by Okoye Ifeoma, 2009.
Rewritten by Leonard Pelletier, 2011

Information Architecture (IA) is the art and science of creating organizing structures around sets of information that make that information easier to navigate. Information Architecture has been around as long as humans have had information to remember, predating literate societies. However, it has taken on even more importance today, in the Information Age.

Before Computers

The Catholic Rosary

Information Architecture is much older than the digital age, even predating the written word. As long as people have been recording information, there have been ways to organize this information. Pre-literate cultures passed information orally, which limited the quantity of information they needed to organize. To maximize their oral memory, oral cultures used simple objects to assist in remembering information and chronology. Songs, bead necklaces, totem poles, and tattoos helped oral cultures remember events and their order long after they have occurred. An example of such a system that is still used today are prayer beads, such as the Catholic Rosary or the Islamic Misbaha.

After the invention of literacy, the quantity and complexity of stored information increased. Perhaps the most important advance in early Information Architecture was the transition from scrolls to books. Books, with their individual pages, are significantly easier to search for their readers because you can open the book at any given page without first having to go through the previous pages.

The book that is generally attributed to shifting the storage of written words from scrolls to books in the Western world is the Christian Bible. The Bible itself has an elaborate IA built into it. All verses are divided into chapters, indexed by two values: a book name and a verse number. For example, the the longest chapter in the Bible is Psalms 119. This is the 597th chapter, located in the book of Psalms, paragraph 119. This IA makes it quite easy for anyone to search through a copy of the Bible to find this information.

As the amount of written information grew, societies began organizing large collections of books in libraries. Modern libraries use the Dewey Decimal System IA to organize how books are stored to allow readers to quickly retrieve them from vast collections of books. Books are classified and sub-classified into various subsets of knowledge, and assigned a number based on that classification. The number corresponds to a place on a shelf in the library where that book can be retrieved from and returned to after it is read.

Vertical and Horizontal Forms

Modern books often contain two ubiquitous forms of IA: a table of contents at the front, and an index at the back. Like the verses of the Bible, the table of contents is a sequential listing of the topics and sub-topics of the book, and a corresponding page number where each topic begins. An index is a listing of where specific keywords appear in the book. Indexes are organized alphabetically rather than by the order topics appear in the book, and allow a more fine-grained search of specific ideas so large that they might appear across many different chapters, or so small they might appear on only one one page.

Table of contents are an example of a heirarchical or vertical organizational structure, whereas an index is an example of a non-hierarchical or horizontal organizational structure. A table of contents breaks a book into a logical sequence of topics and subtopics, creating a searchable hierarchy. However, some ideas might reoccur in many different parts of this hierarchy. For example, the table of contents of a Canadian history textbook might divide the book into chapters organized around various time periods such as World War I, The Great Depression, World War II, and so on. Therefore, the hierarchy of the book is based on chronology. However, if you wanted to search for information on Anglo-French relations, you would need to read through every chapter because this idea reoccurs throughout the chronology of Canadian history. The index, like all horizontal organizing structures, cuts across the layers of the hierarchy and helps you find specific pages in many chapters that discuss this idea.

The World Wide Web

A Typical Sitemap

The Internet represents the largest set of information ever assembled by humanity, and it is usually experienced through the World Wide Web. The Web is an interconnected system of pages of text, images, and multimedia. You are reading a web page right now.

The Information Architecture of the Web grew out of the Library Sciences, and therefore shares a lot in common with the IA of books. Like books in the Dewey Decimal System, all web pages have a unique address known as a Universal Resource Locator (URL), which allows the reader's computer to retrieve the web page from whatever computer in the world hosts it. However, unlike the Dewey Decimal System, there is little organizational structure built into these addresses. The address is only useful for retrieving that resource once you know it exists, and not very useful for finding it if you don't know it exists. Web pages can have their own connections to other web pages however, as hypertext links allow you to jump from one site to another. This system of organization on its own is inefficient and chaotic.

In the 1990s - early days of the Web - it was common to find people creating vertical IA for the web. Internet directories, such as the Yahoo Directory, were maintained by individuals and organizations that strove to create a vast table of contents for the entire Web (or for specific subtopics on the Web), creating lists of credible websites on various topics. At the same time, others tried to a create horizontal IA, creating a searchable index of keywords on the Web. This gave rise to search engines such as Google. As the web grew exponentially, with vast amounts of new information being added by the second, it become difficult for people to maintain large-scale multi-topic directories. The technology that made it possible for search engines to automatically index web pages by keyword, however, was able to keep up to speed. Today, Google is synonymous with searching the World Wide Web, and is the primary IA people in the Western world interact with online. In countries with dictatorial governments such as China, similar search engines are prevalent, but they have back doors that allow the government to censor search results.

IA also exists on a smaller scale on the World Wide Web, built into each specific website. Here, vertical approaches become manageable again, and websites are often organized hierarchically by topic. Site maps and menu systems offer a table-of-contents-like IA for individual sites. Sites may also have a search by keyword feature, like an index, powered by a search engine.

Web 2.0

A Typical Tag Cloud

As Web 2.0 technologies began empowering people to become creators of content, not just consumers of it, new forms of IA have begun forming. One of the most ubiquitous Web 2.0 creations is the Blog, an online journal of posts from an author or set of authors. Blog posts are organized chronologically, with the newest posts appearing at the beginning of the blog, and older ones being pushed down. Blog posts are often tag with specific categories, however, and the blog software generates a directory of all posts with similar tags. This is often in the form of a tag cloud. Tag clouds are lists of categories organized alphabetically, but also use font size to give an indication of the number of posts that are in each category. A blog with many posts on "cute cats" will have the "cute cats" category show up in larger letters than categories with fewer posts. Thus, at a glance of the tag cloud, you can get a sense of the major topics discussed in the blog, as well as search for these posts.

Social Media, another Web 2.0 staple, has also lead to new forms of IA. One of the most widely used is social bookmarking. These services, such as, allow users to save websites for future retrieval. Users must tag each website they save with categories. Each user also has access to the entire community's set of bookmarks, and can search by category to see what other websites are being tagged. Search results can be sorted by popularity, so that the most tagged websites are displayed first. In theory, the most popular sites for that category will also be the most useful and informative. In this way, social bookmarking generates a self-updating and self-correcting vertical IA for the web. It has become a community activity, rather than the work of a single individual or organization.

The Semantic Web (Web 3.0)

The World Wide Web is currently designed to make it easy for to understand and share information. The next iteration of the world wide web, called the semantic web, is widely expected to make it easy for machines to understand this information as well. While machines can currently search for patterns on the Internet, they have no understand of the information in these patterns. For example, a machine cannot differentiate between a legitimate news article written in the New York Times and a satirical article written in The Onion. What effect might this have on IA? As an example, in a semantic blog tagging your posts would be made obsolete. The blog would be able to understand the meaning of the information and categorize it accordingly.

The semantic web promises a more invisible IA that works more intelligently than any previous search technology, but it remains to be seen how quickly these promises will be realized, if at all.

See also

The effective Web design paradigm
web-based strategies
Web design Process
IA Tutorial
Software design
Content Management Systems
Effective Web Design Pardigm
Effective Web Design for A Teenage Audience


Beaird, J., (2007). The Principles of Beautiful Web Design. Collingwood: SitePoint Pty. Ltd.

Bolter, J., (2001). Writing Space. Hillsdale: Lawrence Erlbaum Associates.

Kalbach, J., (2007). Designing Web Navigation. Sebastopol: O'Reilly.

Morville, P., & Rosenfeld, L. (2007). Information Architecture for the World Wide Web. Sebastopol: O'Reilly.

Ong, W., (2002). Orality and Literacy. New York: Routledge.

External Links

IA Institute
Information Architecture Defined
Jakob Nielson's Alert Box
Information Architecture: from craft to profession