Link Overview

Overview

Hyperlinks are at the heart of the web; it is critical that they be functionally accessible to all users. The text content of a link must provide a clear indication of the destination of the link. Links with the text "click here" or "more" are ambiguous when taken out of context and force users to examine content surrounding the link to infer its probable destination. This is a minor annoyance to sighted users, but a major problem for speech reader users.

Text surrounded by graphics may readable by sighted users; however, a user relying on a speech reader will be confused by the jumbled document order and unlikely to find the important contextual content. The result is speech users following unrelated links or missing a useful link and therefore creating a generally frustrating user experience.

Links that open pages in new windows, using the target attribute of a elements, is also a problem. Many developers do this for links that take users to external websites, assuming that the user may return to the original window to resume browsing the original web resource. This destroys the browsing history of the user so that the user cannot use the "back" key to return to the linking resource. This is especially a problem for screen reader users who may not have been warned of the window change or have missed the warning that a new window was opened. They can easily become confused when the "back" button does not take them back to the linking resource. It is important to note that most graphical browsers allow users to decide if they want to open up links in new windows. Moreover, opening new windows adds to desktop clutter and confusion.

Benefits to People with Disabilities

1. Screen reader users can easily identify destinations of links.
2. Not setting the target attribute of a elements to "_new" prevents the confusion and frustration of screen reader users over the flow of the browsing history so that navigation is easier.
3. When alt attribute content is defined and describes the destination of the image link, image links are more accessible to screen reader users. Also, the alt attribute content can be rendered instead of the image by some graphical browsers, resulting in better accessibility.

Benefits to All Users

1. Link text that clearly communicates the target of the link makes navigation easier.
2. When setting the target attribute of a elements to "_new" is restrained, the user has the control over where to open links in, so that the user has better awareness of the browing history.
3. Links will be more completely accessible to users on a wider range of technologies.

Benefits to Developers

1. Using link text that indicates the target of the link makes it easier to find and update links on web resources.

Related Resources

1. W3C WCAG 1.0 link techniques
2. 18: HTML links - let's build a web! (Opera Web Standards Curriculum)

HTML Markup Details

a element

The a element is the main element used to create hyperlinks in a web resource.

It is critical that the text associated with the link clearly indicate the target of the link. Uninformative link text like "click here" or "more" should not be used.

The same link texts should not point to different web resources and different link texts should not point to the same web resource.

alt attribute

Any time an img or area element is used to create a link, the alt attribute content should not describe the image, but instead describe the target of the link.

Related Accessibility Requirements

Illinois Information Technology Accessibility Standards

1.5 Use lists to identify series of related items, including navigation menus.

4.1 Provide appropriate "alternate text" for all images.

9.1 Ensure that links are understandable out of context.

9.2 Provide a means of skipping past repetitive navigation links.

9.3 Avoid using small links.

9.4 Ensure that same-page links move keyboard focus as well as screen focus.

Section 508

1194.22 (e) Redundant text links shall be provided for each active region of a server-side image map.

1194.22 (f) Client-side image maps shall be provided instead of server-side image maps except where the regions cannot be defined with an available geometric shape.

1194.22 (o) A method shall be provided that permits users to skip repetitive navigation links.

W3C Web Content Accessibility Guidelines 2.0

2.4.4 Link Purpose (In Context)

2.4.9 Link Purpose (Link Only)

3.2.4 Consistent Identification

W3C Web Content Accessibility Guidelines 1.0

1.2 Provide redundant text links for each active region of a server-side image map. [Priority 1]

9.1 Provide client-side image maps instead of server-side image maps except where the regions cannot be defined with an available geometric shape. [Priority 1]

9.4 Create a logical tab order through links, form controls, and objects. [Priority 3]

13.1 Clearly identify the target of each link. [Priority 2]