1. He is not dumb.
2. He will play a significant role in how CSS and the web in general develop over the next few years.
3. 1 + 2 = a good thing for all of us
So you may want to at least bookmark his blog.
He brought up an obvious point that I’ve completely missed (which is not unusual for me). That has sparked the following rant.
Alt text serves a key purpose. It’s not just some words that pop up as a toolbar over an image if you leave your cursor there too long. Nor is it just some quick means to identify the contents of an image for text-based browsers or screen readers.
Alt text is one of the many underappreciated keys in HTML that allows an HTML document to be self-contained and self-sustaining long after all the external objects the HTML document reference are gone.
What do I mean by that?
When all that is left is your HTML, will your page retain all the information and meaning it once presented when all those resources were still available?
Here’s the scenario: hundreds of years from now a digital archeologist is combing through a bunch of ancient hard drives recently recovered from the ruins of a long lost data center. A reconstruction team is able to recover data off these terribly large, terribly small capacity disks. That data are your HTML documents. Sadly, the images folder is too corrupted for repair, and only the HTML files themselves are left behind. The documents talk of great accomplishments and amazing and unexpected results that will set the company in a new and exciting direction. But the exact nature of what is being discussed is within those images. The context of the words is lost because the images containing the key information are gone, and there is nothing that describes what was in those images. Sadly, the archeologists put the data into storage, in the basement of some digital museum, and the world will never learn about how your dazzling new CSS-based layout helped increase ease-of-use and, in turn, profits, earning you employee of the year.
If only you had included descriptions of each image within the alt text… the archeologists would go on the news about their amazing find, about how you were the digital god of the early computing age. Several statues would be erected in your honor, and 3 elementary schools (and 1 pre-school) would be named after you.
But that is not to be.
Now this bit of story is fun, but it makes the assumption that you care about how your information is understood hundreds of years from now.
Alright. Let’s talk about right now.
You’ve just developed your amazing web site design. It blows the world away. It’s so hot even Slashdot links to your company. But.. uhoh.. your company has just been hit by the Slashdot Effect. Your image server is dead. Your document server is slowing spitting out HTML. People are able to somehow get to your site, but those images won’t be loading anytime soon. So what are your potential fans (and customers) going to be able to see? No graphs. No screenshots. If there’s no alt text, there’s nothing to ground the surrounding text. People will dismiss your content as useless, make up their own minds and fill in very large blanks with their own misunderstanding of what you’re trying to say.
There goes that employee of the year award. The statues. The schools… well, you get the idea.
The point is this: clients will not always have access to the external resources your document references.
So what about stuff that’s image-centric, such as color blindness tests, or “magic-eye” images or examples of optical illusions? Well you can use text to describe each one of those. That’s your alt text. Will the client be able to get the same use out of the page if it can’t “see” the images? No.. but there’s a difference between use and information.
I may not be able to see the color-blind test image, but reading a description along the lines of “an area filled with different colored dots organized in a pattern such that people who suffer from type X color-blindness will see the number 7 and others the number 8” is sufficient enough information for non-visual users to act upon.
Running out of brain juice again. Please keep in mind all of these random posts of mine are pure stream-of-consciousness (thus the poor organization, spelling, grammar, etc…)
It’s about information. Screw presentation. Hah!