Chapter 15: Thinking about Your Visitors and Your Site’s Usability
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• Conventional uppercase and lowercase text (like the sentence in this book) can be read significantly faster than all uppercase text.
• Right-justified text (also called align=”justify”) is more difficult to read than text with a ragged right margin. • Uppercase characters are most effective for drawing attention to items (and don’t forget small-caps in this regard). • Optimal spacing between lines is at least equal to the height of the characters them selves, and you can adjust this with line height in CSS. I almost always use at least a line-height of 1.25 to open up my design a little bit.
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A liberal use of CSS styles on your Web sites ensures that all your text is displayed attractively and in a manner that is as user-friendly as possible.
In addition, the graphics you include on your Web site should not only convey useful informa tion or design elements, they should be maximally effective. Here are some things to consider when you design graphics for your site: • Context of the graphical elements: All visual metaphors and other graphical elements should be thematically consistent, including whether they are two- or three-dimensional and whether they are color or black and white. (A visual metaphor is a set of images or a picture that represents a certain function. The trashcan on your computer desktop, for example, is a visual metaphor for the file deletion function in the operating system.) To ensure a consistent graphical theme, a site that’s built around a mockup of the Windows user interface shouldn’t suddenly have buttons that look like they’re pulled from an auto dashboard or a children’s toy. • Task domain: Not all applications that can have graphics should have graphics. Although graphical representations of data are often preferred, some types of data are best pre sented as a text table, such as a month-at-a-glance calendar format. • Graphic form of the element: Choose either concrete representations of objects (photo graphs or finely detailed illustrations) or abstract representations (line art and symbols) to ensure consistency. • Extent to which elements can be discriminated in the overall design: Having a series of icons or graphical elements with similar appearance just serves to confuse the visitor.
Another important issue is consistency, which I have woven through the different sections here. Whatever rules you choose to follow, do your best to ensure that your text, graphics, phrasing, and overall design are as logically consistent as possible.
Choice and uses of color One final area to consider on page and site design is your use and application of color. Not only does color have significant cultural meaning that varies as you travel through the world, but you should also consider physiological issues. Bright red on bright blue and light grey on yellow, for example, are almost completely unreadable combinations on a computer screen.