The Intersection of Usability, Accessibility, and SEO (Part I)

February 25, 2009

What could Usability, Accessibility, and SEO (search engine optimization) have in common? Besides industry jargon that website designers/developers need to know, they are in some ways three aspects of the same process.

How can this be; one is making the site easy to use for the average visitor, one is for serving disabled visitors, and the last is to get the site to do well in search engine results. If you really think about it, they are all forms of usability; only the latter two serve special audiences—the disabled, and search engines. This is of course somewhat simplistic though there are many differences they are not completely unrelated.

Something else all three have in common is that extensive thought and planning needs to be done at the very beginning of a website development project for it to be successful in these three areas. While most website publishers (the website developer’s clients) will put some thought into usability, whether the consciously realize or not, they won’t put much thought into search engine optimization, and even less into accessibility (unless they are in an industry in which there are accessibility requirements). Deciding the site needs to accessible, or perform well in search engine results will be time consuming (which equals expensive) if only considered in the middle, or after the completion of the website project.

While content can be rewritten to optimize a site for search engines, recoding a website for accessibility can involve drastic reengineering later. Of particular concern is the accessibility of client-side scripting used to produce Rich Internet Applications, particularly Asynchronous JavaScript and XML (Ajax).

A major difference between sighted website visitors, and those using Assistive Technologies (AT) such as screen readers, is sighted website users have random access to the information—the ability to look around the page and read the content in any order, and when it comes to AJAX, see dynamic changes. A website visitor using a screen reader will tend to "read" a page in a linear fashion, and depending on the AT used, not get any cue that the content has changed via AJAX, if they can even trigger the change.

While screen reader software has gotten better in its ability to handle JavaScript, there is still a wide variance in how well they work. People using AT also tend to upgrade slowly due to a number of factors, including cost, as well as the hurdle of having to learn new software—not necessarily the easiest thing to do when you have to memorize every keyboard command.

With SEO on the other hand, the issue with retrofitting is knowing the correct parameters. As opposed to popular misconceptions, SEO is as much about researching, and selecting the correct keyword phases to optimize the site for, as much as anything else. If you haven’t taken the time to figure out what terms your potential site visitors are searching by, you can’t properly optimize a website for search results. Only once the best terms are figured out, can the website be optimized be optimized by including the phrases in specific parts of each webpage. Successful SEO, at least the on-page portion of organic SEO) requires either writing copy to appeal to search engines (by including the search terms), or rewriting the copy on an existing website.

In the end, the best strategy is to figure out the goals of the project at the start, and determine the importance of Usability, Accessibility, and SEO, since they will all come with a price, which may come in the form of time, money, simplified design, or a reduced feature set.

Next time, I’ll share Usability, Accessibility, and SEO resources.