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"Alt text" for images

To make the site more accessible to people, such as blind people, who use screen readers the Mediawiki software that runs this wiki allows people to add "alt text" tags to images.

These alt text tags work as follows. When a blind person wants to read a web page, they frequently use a piece of software called a screen reader. This screen reader reads the text on the web page to them, so that they can listen to the page rather than viewing it. The system works well for most wiki pages because wiki pages are frequently very text based. However, when images are involved, the screen reader software isn't smart enough to be able to describe the contents of the picture (a human is required for that). In this case, we need to provide "alternative text," known as "alt text" for the screen reader to read to the user so that the user knows what the picture is of.

Mediawiki, the software that runs our site and that also runs Wikipedia, has support for "alt text" built in. To make the site accessible, all that we need to do is include a little bit of text whenever we add the picture. For example, consider the following text, used to add a picture of David Schechter:

[[File:Practitioner David Schechter.jpg|alt=An image of Practitioner David Schechter]]

The above code to include a picture consists of the following;

  • "File:Practitioner David Schechter.jpg" is just the name of the file.
  • "alt=An image of Practitioner David Schechter" is what gets read by screen readers to help them know what is in the picture
  • The "[[," "|," and "]]" are just used to keep the other elements apart.

As of November 27, 2011, we do not yet have a help pages for more information on how to include images. However, more information is forthcoming.

More information about Mediawiki and accessibility

The following web pages can be used to learn more about making Mediawiki web sites more accessible: (see the note below, though)

Some of the above sources may be complicated and frustrating to the casual reader because there are two levels of making a wiki more accessible. The first level involves using the functionality that is built into the software. A good example of this is including alt text such as is described above. The next level involves hacking Mediawiki to change it's functionality in ways that the original programmers didn't intend. Of course, if there were easy ways to modify Mediawiki to make it more accessible, the programmers, who tend to be generous people, volunteering their time, would have already included these modifications in all Mediawiki installations. As a result, those modifications that they don't include often tend to be exceedingly technical (they also sometimes decrease usability for non disabled visitors). Because of the hacking involved, learning about these more complex accommodations may require a detailed understanding of technology.