Sunday, November 05, 2006

Accessibility, usability, inability, etc.

I was going to write a fantastic post about website accessibility and usability, but it's taking too long and going nowhere and I'm rapidly losing the will to live, so let's just call it a day and say this:

If you have a website and use images, please write ALT text for them so that people with low or no vision (who use text readers) or those who have turned off pictures (to minimise download size on slow or limited internet connections) will know what you're trying to show them. To write ALT text, find the image links in your html (in Blogger you'll find this in the Edit Html window, strangely enough) and then between the quotation marks at alt="" type a description or explanation of the image. For example, if you can see the following photo and can hover a mouse over it...

Photo by Deirdre: happy white clouds in a springtime blue sky
... you won't need me to tell you that the ALT text says "happy white clouds in a springtime blue sky", and it says that because I'm just an old hippy, yes.

There are lots of things to consider when designing an accessible blog/website, most of which I've never considered, and am only considering now because I got lost while trying to find information on link colours and ended up wandering through the archive of articles written by Jakob Nielsen: Current Issues in Web Usability. (I love the way that happens! Serendipity, etc. God bless the internet! Everybody should get the chance to get lost like this.)

Anyway, Nielsen highlights include:

- Accessibility Is Not Enough (2005)
[...] it's an oversimplification to distinguish between users with and without disabilities as if that were a dichotomy. It's really a continuum of people with more or less severe disabilities. For example, most users over the age of 45 have somewhat reduced vision and need resizable fonts, even if they don't qualify under the official definition as "low-vision users." Senior citizens' usability issues are different from those of young users with disabilities, but again, there are many similarities between the two groups.

- Beyond Accessibility: Treating Users with Disabilities as People
Our report documents numerous design flaws that reduce the Web's usability for users with disabilities. In other words, changing the designs to comply with the usability guidelines would reduce the difference in usability for users with and without disabilities. We are not stuck at the current level -- things can get better.

- Participation Inequality: Encouraging More Users to Contribute (2006)
In most online communities, 90% of users are lurkers who never contribute, 9% of users contribute a little, and 1% of users account for almost all the action. [...] There are about 1.1 billion Internet users, yet only 55 million users (5%) have weblogs according to Technorati. Worse, there are only 1.6 million postings per day; because some people post multiple times per day, only 0.1% of users post daily.
Blogs have even worse participation inequality than is evident in the 90-9-1 rule that characterizes most online communities. With blogs, the rule is more like 95-5-0.1.

- Usability for Senior Citizens (2002)
Websites tend to be produced by young designers, who often assume that all users have perfect vision and motor control, and know everything about the Web.

- Usability of Websites for Teenagers (2005)
Teenagers are not in fact superior Web geniuses who can use anything a site throws at them. We measured a success rate of only 55 percent for the teenage users in this study, which is substantially lower than the 66 percent success rate we found for adult users in our latest broad test of a wide range of websites.

- Kids' Corner: Website Usability for Children (2002)
Young children often have hand-me-down computers, whether at home (where they often inherit older machines when their parents upgrade) or at school (where budget constraints mandate keeping machines in service for many years). Kids also typically have slow connections and outdated software. Given these limitations, websites must avoid technical problems or crashes related to access by low-end equipment. Faced with an error message, kids in our study told us that they see them a lot, and that the best thing to do is to ignore them or close the window and find something else to do.

- Lower-Literacy Users (2005)
Based on the available information about Internet participation at different education levels, I estimate that 30% of Web users have low literacy. Because most of the higher-literacy population is already online, however, future growth in Internet usage will mainly come from adding lower-literacy users. Thus, in five years or so, lower-literacy users will probably be 40% of Web users.

So. That's it. The end. A long post, badly put together. Thank you and good night, reader. In a manner of speaking. ("In a manner of speaking"? What the hell does that mean??) Etc.