Research

Whitespace

One study found that double spacing may be preferable to single spacing on the web for increasing readability (Kolers, 1981). According to Zibel, one of the definitions of a readable web page is that it is "not text heavy and makes effective use of whitespace" (Zibell, 2000).

Line length is a related issue to whitespace. Researchers found that subjects prefer shorter to longer line lengths on a page (Ling, 2005). A different study found that line lengths should considered in relation to the purpose of the text used. Shorter line lengths should be used when there is dense information that must be read carefully and longer line lengths should be used for text that should be scanned quickly (Dyson, 2001). However, both extremely short and extremely long line lengths slow down reading by altering the pattern of reader eye movement (Dyson, 2001).

Font Color

Previous print research has shown that black font on a white background is more readable than white font on a black background. The contrast of black and white colors in print and screen is referred to as polarity (Mills, Weldon,1988). One study found that font color plays a big role in the readability of text on a page because it creates visual consistency. Viewers associated and are better able to make connections between concepts on a page when different, logical font color choices are made (van der Geest, 2005).

Uppercase vs. Lowercase

Although more research is needed on whether uppercase or lowercase is more readable and legible online, studies involving print have found that the purpose of the text is the more important criteria in determining whether uppercase or lowercase is appropriate. Uppercase letters are appropriate for headings, and when someone needs to see text from a distance. In contrast, when someone is reading "continuous text," lowercase is preferable (Mills, Weldon, 1987). In other words, while uppercase is good for increasing text legibility, lowercase is preferable for creating high readability.

Fixed vs. Variable Character Width

Typewritten letters generally all have the same width. For instance, an i and l would have the same width measurement. One study found that people read text with variable width characters slightly faster than text with fixed width characters (Beldie, 1983). However, another study found that whether character width is fixed or variable has no affect on readability (Muter, 1982). This is an area in need of more research.

Guidelines