Jonathon Delacour the heart of things

Building Accessible Websites, by Joe Clark

Building Accessible Websites comes highly recommended. In late October, Mark Pilgrim wrote:

Joe Clark’s Building Accessible Websites is now shipping. I was one of the technical editors for this book; having read it thoroughly, twice, I can assure you that it is the most comprehensive and most well-written web accessibility book in existence. Every web designer should read it. If you can only afford one web accessibility book, buy Joe’s book. (If you can afford two, buy Joe’s book and Jim’s book, reviewed here.)

When Joe emailed me to ask if I’d be interested in reviewing his book, I readily agreed—I have a strong interest in website accessibility (largely triggered, I confess, by the experience of making my own site accessible by implementing the tips in Mark’s series, Dive Into Accessibility: 30 days to a more accessible web site). Joe also agreed to answer a series of questions about the book and, more generally, about accessibility. I’ll publish this extended interview in a series of posts over the next few days.

The structure of Building Accessible Websites is much as one might expect. After briefly explaining how he intends the book to be read, Joe Clark runs through “some typical objections to providing accessibility, blowing them out of the water one after another,” then lists a number of active reasons for making one’s site accessible. He outlines the various kinds of disability (hearing-, vision-, mobility-, and learning-related), explains how disabled people use computers, and defines both accessibility and the structure of accessible pages.

Having mapped out—in five relatively brief chapters—the nature and extent of the problem, Clark gets down to the nitty-gritty: how to make images, text & links, navigation, type and color, tables & frames, stylesheets, forms & interaction, and multimedia (including Flash) all accessible.

The chapters on images and navigation are much longer than any of the others, reflecting Clark’s belief that addressing these two issues—even at a basic level—will make a site “vastly more accessible” to two large disability groups: the blind and visually-impaired and the mobility-impaired. (Clark’s Slashdot interview, which appeared last week, is essential reading for anyone interested in accessibility.)

These how-to chapters are all structured similarly. For example, Chapter 6, The Image Problem, covers:

• the three levels of accessibility for uncomplicated image types (the alt, title, and longdesc attributes);
• variations in browser support for each attribute and workarounds;
• problem image types including advertising, animated GIFs, bullets, charts & graphs, exploded drawings, hit counters, maps, pictures of text, porn, image portfolios, rollovers, sliced graphics, spacer images, and webcams);
• succinct advice on implementation; and
• a supplementary section with more hints on making online ads accessible.

A section titled Bottom-Line Accessibility Advice concludes each chapter. For example, the advice for images is:

Basic accessibility

Use alt texts on absolutely every image without exception.

Intermediate accessibility

Add titles to images in increments no smaller than a page: Either all graphics on a page contain titles or none.

Advanced accessibility

Write long descriptions for the rather more intricate images.

In the last two chapters, Clark discusses certification & testing and outlines some “future dreams.” Finally, he provides appendices on accessibility & the law and language codes, a bibliography, and a colophon (describing the making of the book). In addition, the entire text of the book is included on the accompanying CD-ROM, making it easy to search the book’s contents and to check the code samples—you simply copy the code into an editor then view it in a browser.

Although I hope by this point I’ve convinced you that Building Accessible Websites is comprehensive and full of practical advice, those are not the only reasons the book is worth buying and reading. Mark Pilgrim is absolutely correct when he says: “Joe’s an incredible writer; he can explain the most esoteric topics in a way that anyone can understand.” And it’s not just that he writes with great clarity and elegance. A large part of the book’s appeal is Clark’s refusal to pull any punches:

Usability is a good predictor of accessibility, since usable sites are put together by intelligent, thoughtful people (not necessarily paid experts), and that is exactly the group that pays heed to access without being pushed and prodded. But we should not expect a one-to-one relationship. Usable sites can be inaccessible (e.g., an E-commerce site where every navigation button is an image without a text equivalent). Conversely, accessible sites can be unusable - e.g., Jakob Nielsen’s Alertbox.com, which is so outlandishly undesigned as to make it hard to find anything, not to mention dozens or hundreds of pages at the World Wide Web Consortium itself, where we similarly drown in accessible data.

Frequently provocative, Joe Clark is also remarkably pragmatic. For example, it’s almost an orthodoxy in Blogaria that table-based layouts are inferior to those that use CSS-positioning. Not so, argues Clark:

The use of tables for layout has never been prohibited by the Web Accessibility Initiative. You are not creating an inaccessible page if it contains tables used for layout. You have committed no sin—necessarily. You will not be forced to turn in your trackball and badge while WAI Internal Affairs conducts an investigation. But you are not off the hook: You must code tables properly, which, for layout tables, is not difficult at all.

He is similarly relaxed about pictures of text:

For small amounts of text (typically, text rendered as graphics is used for navigation buttons), enter the complete text into alt; you can add explanatory details to title if you wish. (Example: alt=”Contact” title=”Contact information, job listings, and feedback page”.) Accessibility purists may hate this entire approach, but I simply do not see any harm whatsoever in limited bits of text rendered as graphics since it is dead simple to make those graphics accessible. I use pictures of text myself.

Though I nearly fell off my chair when I read Clark’s advice on headings:

The Web Content Accessibility Guidelines tell us to use heading elements in strict numerical order—<h1></h1>, then, if necessary, <h2></h2> through <h6></h6> in that sequence. That dictum suits androids and Vulcans quite well, but here in the real world you can skip intervening levels and you don’t have to start at <h1></h1>. I am telling you that you can defy the WCAG in this limited way. You must not, however, use heading elements in anything but ascending order.

Call me a Vulcan—or an android—but this makes no sense to me at all. The usual reason given for starting with (say) <h3></h3> is that <h1></h1> is too big, black, and ugly. Yet you can easily define the appearance of any element with CSS so the <h1></h1> can be as small, brightly-colored, and pretty as you like. More importantly, assigning <h1></h1> to the first heading on a page will assist in securing a higher Page Rank in Google. And why would you want to skip intervening heading levels? In other words, what’s the advantage in defying the WCAG in this case?

I was also surprised at Clark’s advice concerning resizable text, particularly when I recall the angst that accompanied my switch from pixel-based to relative font sizing. Clark argues that anyone with significant visual impairment will be using screen magnification software, thus rendering the font-size argument irrelevant. While I can see his point, I still believe that it’s worth accommodating normal-vision people who find small type difficult to read, even if it is “too low-level for this book to worry about.”

So, what’s that then? A couple of quibbles in over 400 pages. Mark Pilgrim was right: Building Accessible Websites is the book to buy. (Jim’s book, to which Mark also referred, is Constructing Accessible Web Sites by Jim Thatcher et al.) It’s a fine book, packed with useful information. But, because it has eight authors, it lacks the most appealing quality of Joe Clark’s book: the sense of being guided through the subject by an informed, literate, entertaining, and—above all—iconoclastic expert who absolutely fulfills his own aspirations for the book:

You will, I hope, find the book quite readable. I have this fantasy that Building Accessible Websites will be as enjoyable to read as a well-written cookbook. (What, you’ve never read a cookbook while reclining in bed, far removed from the kitchen?)

I’m not a great reader of cookbooks (I’m not much of a cook, for that matter, though I discovered tonight I can cook a trout to perfection). But I did find myself reading Joe Clark’s book in bed and almost everywhere else in my house—as well as on the train and in a couple of my favorite restaurants. Building Accessible Websites is a considerable achievement: a thorough practical guide to Web accessibility that’s also a pleasure to read.

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