Understanding Success Criterion 2.4.1 [Bypass Blocks]
Intent of this Success Criterion
The intent of this success criterion is to allow people who navigate sequentially through content more direct access to the primary content of the Web page. Web pages and applications often have content that appears on other pages or screens. Examples of repeated blocks of content include but are not limited to navigation links, heading graphics, and advertising frames. [begin add]Small repeated sections such as individual words, phrases or single links are not considered blocks for the purposes of this provision. [1994] [end add]
This is in contrast to a sighted user's ability to ignore the repeated material either by focusing on the center of the screen (where main content usually appears) or a mouse user's ability to select a link with a single mouse click rather than encountering every link or form control that comes before the item they want.
Specific Benefits of Success Criterion 2.4.1:
When this success criterion is not satisfied, it may be difficult for people with some disabilities to reach the main content of a Web page quickly and easily.
Screen reader users who visit several pages on the same site can avoid having to hear all heading graphics and dozens of navigation links on every page before the main content is spoken.
People who use only the keyboard or a keyboard interface can reach content with fewer keystrokes. Otherwise, they might have to make dozens of keystrokes before reaching a link in the main content area. This can take a long time and may cause severe physical pain for some users.
People who use screen magnifiers do not have to search through the same headings or other blocks of information to find where the content begins each time they enter a new page.
People with cognitive limitations as well as people who use screen readers may benefit when links are grouped into lists
Examples of Success Criterion 2.4.1
A news organization's home page contains a main story in the middle of the page, surrounded by many blocks and sidebars for advertising, searching, and other services. There is a link at the top of the page that jumps to the main story. Without using this link, a keyboard user needs to tab through approximately 40 links to reach the main story; the screen reader user has to listen to 200 words; and the screen magnifier user must search around for the location of the main body.
Related Resources
Resources are for information purposes only, no endorsement implied.
(none currently documented)
Techniques and Failures for Success Criterion 2.4.1 [Bypass Blocks]
Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this success criterion. The techniques listed only satisfy the success criterion if all of the WCAG 2.0 conformance requirements have been met.
Sufficient Techniques
Creating links to skip blocks of repeated material using one of the following techniques:
G1: Adding a link at the top of each page that goes directly to the main content area
G123: Adding a link at the beginning of a block of repeated content to go to the end of the block
G124: Adding links at the top of the page to each area of the content
Creating HTML links to skip blocks of content (future link) [2100]
- [begin add]
Providing a link to "jump to top of page" if the repeated material is at the bottom of the page [1950]
[end add]
Grouping blocks of repeated material in a way that can be skipped, using one of the following techniques:
H69: Providing heading elements at the beginning of each section of content (HTML)
H70: Using frame elements to group blocks of repeated material (HTML) [begin delete] AND Using the title attribute of the frame element [2097] [end delete]
Common Failures Identified by the Working Group
The following are common mistakes that are considered failures of Success Criterion 2.4.1 by the WCAG Working Group.
(No failures currently documented)
Additional Techniques (Advisory) for 2.4.1
Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.
Providing keyboard access to important links and form controls (future link)
Providing skip links to enhance page navigation (future link)
Providing access keys (future link)
- [begin add]
Using accessibility supported technologies which allow structured navigation by user agents and assistive technologies (future link) [1994]
[end add]
Key Terms
- Web page
[begin add]a non-embedded resource that is referenced by a URI plus any other resources that are used in the rendering or intended to be rendered together with it by a user agent [end add] [begin delete]a resource that is referenced by a URI and is not embedded in another resource, plus any other resources that are used in the rendering or intended to be rendered together with it[end delete] [1948]
Note 1: Although any "other resources" would be rendered together with the primary resource, they would not necessarily be rendered simultaneously with each other.
Note 2: For the purposes of conformance with these guidelines, a resource must be "non-embedded" within the scope of conformance to be considered a Web page.
Example 1: A Web resource including all embedded images and media.
Example 2: A Web mail program built using Asynchronous JavaScript and XML (AJAX). The program lives entirely at http://mail.example.com, but includes an inbox, a contacts area and a calendar. Links or buttons are provided that cause the the inbox, contacts, or calendar to display, but do not change the URL of the page as a whole.
Example 3: A customizable portal site, where users can choose content to display from a set of different content modules.
Example 4: When you enter "http://shopping.example.com/" in your browser, you enter a movie-like interactive shopping environment where you visually move about a store dragging products off of the shelves around you into a visual shopping cart in front of you. Clicking on a product causes it to be demonstrated with a specification sheet floating alongside.