Applies to all technologies
This technique relates to:
The objective of this technique is to provide a way to link to remote long descriptions in technologies that do not have a long description feature built directly into them (e.g. longdesc) or where the feature is known to not be supported.
With this technique, the long description is provided in another location than the non-text content. This could be at another location within the same URI or at another URI. A link to that long description is provided that is immediately adjacent to the non-text content. The link can be immediately before or after the non-text content. If the description is located along with other text then put "End of description" at the end so that they know when to stop reading and return to the main content. If a "Back" button will not take the person back to the point from which they jumped, then a link back to the non-text content location is provided.
This technique was commonly used in HTML before 'longdesc' was added to the specification. In HTML it was called a D-Link because it was usually implemented by putting a D next to images and using the D as a link to the long description. This technique is not technology specific and can be used in any technology that supports links.
There is a bar chart on a Web page showing the sales for the top three salespeople.
The short text alternative says "October sales chart for top three salespeople."
Immediately after the non-text content is a small image denoting a long description. The alternate text for the image is "Long description of chart". The image links to the bottom of the page where there is a section titles "Description of charts on this page". The link points to this specific description: " Sales for October show Mary leading with 400 units. Mike follows closely with 389. Chris rounds out our top 3 with sales of 350. [end of description]"
There is a bar chart on a Web page showing the sales for the top three salespeople.
The short text alternative says "October sales chart for top three salespeople."
Immediately after the non-text content is a small image denoting the
long description. The alternate text for the image is "Long
description of chart". The image links to another page titled
"Description of charts in October Sales Report". The description
link points to this specific description: "Sales for October show
Mary leading with 400 units. Mike follows closely with 389. Chris
rounds out our top 3 with sales of 350. End of description.
<link>
Back to Sales Chart
</link>
]"
There is a chart. The figure caption immediately below the chart serves as a link to the long description. The Title attribute of the link makes it clear that this is a link to a long description.
There is a recording of a speech by Martin Luther King. Links to the audio file and the transcript appear side by side.
Resources are for information purposes only, no endorsement implied.
check for the presence of a link immediately before or after the non-text content
check that the link is a valid link that points directly to the long description of this particular non-text content.
check that the long description conveys the same information as the non-text content
check for the availability of a link or back function to get the user back to the original location of the non-text content
All 4 of the above are true