Principle 3: Keep It Consistent
Newspaper designers have long understood the importance of consistency in their work. Look at the front page of any paper. Although the news may be very different day to day, the page's navigational elements stay in the same place. The newspaper's logo stays at the top. The index is usually fixed in a corner. No designer at a newspaper wastes time worrying if the headlines should run horizontally or vertically. As a result, people feel comfortable with a newspaper and designers don't have to reinvent it every day.
"A foolish consistency is the hobgoblin of little minds." æEmerson
Jakob Nielsen has said, "Consistency is one of the most powerful usability principles: when things always behave the same, users don't have to worry about what will happen. Instead, they know what will happen based on earlier experience."7
For your visitors to benefit, your site will need to follow consistency in both design and interaction. Design consistency includes grid, navigation, link colors, button styles, font usage, control elements and metaphors. Use templates, cascading style sheets, and style guidelines to help manage this task (See Fig. 2.9).
figure 2.9: be consistent
Consistency makes things easier to design. A Web designer doesnÕt have to rethink the navigation or how the page should fit with the overall design. Use templates, cascading style sheets, and style guidelines to help in manage this task.
guide and direct
Navigation and search stay in the same place because customers depend on these elements for finding what they want. Maintaining consistency will build confidence as the customer continues deeper into the site.
act the same
The grid structure and color palette are important elements of creating consistency. Notice that all action buttons are designed the same, and placed in relative proximity to the task.
Interaction deals with the behavior of your site, which should be understandable, predictable and persistent. People don't like to learn things unless they feel they can apply that knowledge in many places. Strive to reduce what a user needs to learn to complete a desired task.
Of course, consistency doesn't guarantee a usable site. Poor visual and interaction design used consistently is still consistently bad design. Consistency has several benefits to your Web site:
Consistency reinforces a sense of place, helping users to know where they are on the site and what to expect next.
Consistency makes things easier to use. Every successful task performed reinforces familiarity.
Consistency makes things easier to design. A Web designer doesn't have to rethink the navigation, the location of content elements on a page, or how the page should fit with the overall design.
Consistency protects design from passing fads by keeping navigation simple and direct.
Consistency reinforces branding.