Images - Section 6
Poor use of images is the greatest cause of basic accessibility failures on the web. Follow this simple guidance to ensure that your site does not prevent many people accessing the contents of your site.
some people can't view images, for example:
- People who are blind who use speech browser (screen reader) software; or
- Braille output software and hardware.
Some people choose not to display images, for example:
- People on slow connections with 'images off'; or
- Users of phones, pdas and text-only browsers.
Some images are often used inappropriately, for example:
- Images that should be text:
- these lose the flexibility that real text has;
- Images in the wrong format:
- these can appear blurred and/or increase download time;
- Images not described properly:
- these are impossible to interpret for people who cannot download the image;
- Images sized incorrectly:
- height and width values should be used to block out space required for displaying the associated image.
In this section:
- DEV 6.1 - All images must have alt text to convey the equivalent information
- DEV 6.2 - Provide full descriptions for informational images
- DEV 6.3 - Avoid using images to display text
- DEV 6.4 - Use the correct image format for the job
Most of the recommendations in this section are common sense.