People who cannot see images can get the information contained in the images when web developers include alternative text equivalents for images.
Web accessibility also provides financial and technical benefits to organizations, as described in the “Additional Benefits from a Business Perspective” section later in this chapter.
There are many more examples of how web accessibility benefits people with and without disabilities throughout this chapter.
For images with alt text provided, the alt text is displayed.
Where alt text is missing (the middle image), "IMAGE" is displayed. Images turned off and alt text showing Figure 1-4 shows the display of IBM Home Page Reader set to read images without alt text.
The markup for image alt text looks like: Alt text is rendered differently by different browsers and configurations, as shown in Figures 1-2, 1-3, and 1-4.
Figure 1-2 shows a page in Microsoft Internet Explorer with images loaded and the mouse hovering over an image, which displays the alt text ("rain") in a pop-up. Common browser showing the alt text “rain”Figure 1-3 shows the same page in Opera with images turned off in the browser settings.
However, this possibility is not reality throughout the Web.
The problem is that most websites have accessibility barriers that make it difficult or impossible for many people with disabilities to use them.
People who are blind can read the newspaper (through screen readers that read aloud text from the computer), and so can people with cognitive disabilities who have trouble processing written information.
People who are deaf can get up-to-the-minute news that was previously available only to those who could hear radio or TV, and so can people who are blind and deaf (through dynamic Braille displays).
These examples are missing alt text for only one image.