(a) IMAGES


checkbox All photos, images and graphics-as-text must have equivalent alt tags.

Alternate text, also referred to as an "alt tag," is a label that describes the contents of a photo or image. Screen readers (programs that read Web pages aloud to blind and low vision users) read this alt tag to the user.

Without the alt tag, the blind web surfer will have no way of knowing what the contents of the image are. This alt tag needs to be added by the person building the Web page. An alt tag should be succinct; usually one sentence long.

Examples:

Globe with keyhole that symbolizes Web accessibility

Image with an alt tag:
<img src="../globe.gif" alt="Globe with keyhole that symbolizes Web accessibility">


Image with out an alt tag:
<img src="../globe.gif">

For images that are purely decorative (ex: a fancy line that divides two paragraphs), an empty alt tag may be used. This tells a screen reader to just ignore the picture.

Example:

<img src="../fancyline.gif" alt="">


checkbox If necessary, create long descriptions of your images using the longdesc attribute.

Sometimes one sentence in the form of an alt tag is not enough to convey the concepts of an image or photograph. An example would be a chart, graph, or technical drawing. In these cases, the long description attribute is useful.

A long description is a separate page that contains a paragraph or more of explanation. It can be as long or short as the web page designer wants it to be. The following outlines the general procedure for creating long descriptions:

1. The designer creates a new page with only the bare minimum on it. Navigation is not necessary. Just type in the long description and save the page as you would any other web page. Nothing too fancy or time consuming.

2. Insert a special HTML attribute (longdesc) that points to that long description page. The link is hidden to everyone else except for web surfers using a screen reader. In the How-To guides, the exact details are laid out depending on the program that you are using.

Example:

election map

<img src="../map.gif" alt="election map" longdesc="mapexplanation.htm">

With that said the longdesc attributes is generally not used. If the details of a complex image need to be explained to someone that is blind, most likely ALL users will benefit from this explanation. Therefore, it is usually a better choice to just include a text-description for all users to see that is next to the picture. Sited users can visually read it and a screen reader will, as well!

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