Seven plus or minus 2 - Helping people process your website

With few exceptions, web information architects generally structure website information with the rule of “seven plus or minus two” in mind. The idea that the human brain best processes information in manageable chunks goes back to the 1950s, when the psychologist George Miller published a paper called "The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information" in 1956.

For menu and list design, in particular, application of the rule is generally considered good practice for site usability. But, with the complexity of websites growing rather than diminishing and the increasing demand to include vast arrays of data, the challenge to maintain this rule is getting more difficult to maintain and leading to interesting solutions. This challenge is well illustrated by news and portal pages that have to provide pathways deeper into the site’s content.

The Yahoo!7 Australia home page provides a good illustration of how visual design, taxonomic skills and the “seven plus or minus two” rule co-operate to create a mostly usable gateway.

The Home page layout exemplifies the kind of layout that is typical of a news website. Below the header, there are three main columns, with the central body column frequently splitting into two columns.  These columns are then broken up with feature panels, tabbed sections, colour strap dividers and horizontal rules that create sub-sections their own navigation options.

When the number rule cannot always be adhered to, supportive techniques aid in offsetting the cognitive load on the user. These techniques include: alphabetical ordering, numbering, icons or graphical cues, and scroll, dropdown and “see more” options. These features allow for optional extension well beyond the recommended number limit. The option to “see more” allows the IA to build in more to satisfy the most demanding list-o-maniac.

The image shows:

  1. The search box. Provides four filtering choices above the search box, with an additional four available through a dropdown list.
  2. The horizontal hearder bar. (below the search box) Provides five options, including the site you’re on to go to other sites associated with Yahoo.
  3. The vertical left hand menu.  This is the principal menu, containing 25 choices to Yahoo! websites. This long list is alphabetised and uses icons.
  4. The services fly-out menu. Below the vertical menu, the fly-out menus provide long lists of services that would otherwise take up precious screen real estate.



These fly-out menus are problematic. Firstly, they usually provide long lists of links under one heading. The lists usually cover three columns, each of which is alphabetised. But why this has been done isn’t clear. The second problem is the fly-out menus themselves, as their relationship seems unclear and therefore random. A more usable solution would be to group these meaningfully. As for the lists, the “Features” would need a sub-heading to give meaning to the multiple, alphabetised lists.

Part of the reason for shorter lists is to keep it easy and usable for the user. But, when the pattern or grouping is unclear, the user needs to think in order to make sense. Sorting out these two things is actually the information architect’s role.