This article is based on research I did for a dissertation on web usability and highlights some of the key areas that make a website easier to use.
The main goal is not to complicate the already difficult life of the consumer – Raymond Loewy
Usability experts agree that, despite what many people may assume, users don’t want a great deal of information. They just want the amount of information necessary for them to complete their task. Users want information quickly and they can become confused or frustrated when something distracts them from their goal.
Users Don’t Read Content, They Scan It
Many website authors make the mistake of presuming that users will take the time to read in-depth content and try to understand how a site is organised. However, users want information quickly. In fact, instead of reading text, they scan it (Morkes & Nielsen). They do this by picking out single words or sentences and extracting only basic information. This allows them to cover larger areas of text in less time. Therefore, web page content should be written in a way that is concise and with logical layout (headers, lists, short paragraphs, etc.).
Strip Down Content
Users pay attention to information that is either relevant to the task at hand, of personal interest to them or to trigger words. These trigger words are ones that we naturally respond to; words like “free”, “sale” and “sex”. Web content can be improved when it is stripped of unnecessary language and when important words or phrases are drawn attention to (hence the bold lines of text in this article).
Headers and sub-headers should give a short but accurate description of the content to follow, using terms that the user is familiar with. Since users normally won’t read a large body of text, paragraphs should be limited to one idea at a time so that they are easily digested.
The Inverted Pyramid
The ‘inverted pyramid’ style of writing, which is often used in journalism, works well on the web. This method of puts forth the most important information at the beginning of the text with additional information following in descending order of importance. This allows the users to easily browse each section and surmise the context then decide on whether to continue reading. In web design, the area under which the user has to scroll down to see (known as ‘the fold’) is of less importance. Another advantage to this writing style is that search engines are more likely to analyse the information closer to the top of the page.
What makes website content different from traditional styles of writing is that information can be easily linked. Text doesn’t need to appear as a linear body of text, but can be separated into individual areas, each linking to one another. Therefore the reader has more control over which path they wish to follow. Since the user is given more power over the direction they can take, there is more need for each area to compete for attention. Again, this interlinking of page can benefit a site’s search engine rankings.
Font size is a common concern with designers. If a font size is too small or too large then the text becomes difficult to read at length. Studies show that common web fonts are read noticeably slower when it is less than 10 point. 12-14 point is considered optimal for most adults, although older people prefer larger font sizes. Sans serif fonts are generally preferred to serif, however there is little evidence to suggest that they effected reading times. An important factor to consider when selecting a font, however, is that the actual text size may differ with fonts of the same point size. The way the font is viewed may also vary depending on user settings, screen resolution and browsers types.
Line length is also an important factor on how quickly users can read text. This is based on the capabilities of the human eye which, at typical reading distance, only has a visual field of a few inches. Reading long lines of text which exceed this distance requires more eye movement and can become tiresome. An investigation by Bernard et al. (2000) concluded that longer line lengths should not be used for web pages, especially those with large bodies of text. Shorter line lengths (around 11 words) are favoured over full-screen lines, as users are more likely to loose their place in the text when reading longer lines. However, very short line lengths are discouraged, as they require the user to scroll down the page. The study concluded that for adults, a typical line should consist of around 65 to 75 characters per line (CPL), whereas children favoured shorter lines (around 45 CPL).
It is a popular opinion of graphic designers that open-space (referred to as ‘white-space’, though not necessarily white) not only contributes to the attractiveness of a design, but provides additional functionality. Areas of white space can be used to organise areas on a page by drawing attention to easily identifiable regions. Important areas can be made to stand out if unnecessary visual elements are reduced to a minimum and information is suitably structured. The use of white space can eliminate the need for artificial barriers such as boxes or bars. White space is useful for, “directing the viewer’s attention to the regions where important information is provided and allowing the global structure of the composition to assume a meaningful configuration”.
A major concern with the usability of web pages is the appropriate contrast between the text and the background colours. This is especially relevant to users who are colour deficit, or “colour blind”. Around 8% of males are believed to be colour blind (myself being one of them). The condition is much less common with females, with around 0.5%. Research shows that in general dark text on a light background results in more accurate reading (Bauer and Covonius, 1980) and that black text on a white background is the best combination.
Researchers agree that black and white produce the most effective contrast for reading, but realise that this is not always suitable for commercial web pages where aesthetics and human psychology play a larger role. Still, darker colours against light backgrounds produce high contrast. People were more likely to find information quickly when the background was plain, rather than textured, although this is not so significant when there is sufficient contrast between text and background.