Understanding Purpose of Controls

Intent

This section contains the main explanatory content of the Understanding. It explains why the Guideline or Success Criterion exists and, at a high level, how to meet it.

The intent of this success criterion is for users to be able to better optimise their experience according to personal preferences or accessibility needs. By providing a means to programmatically determine the purpose of (add: predefined!) common (conventional) controls it’s possible for user agents or other software (or: technologies) to allow users to improve the personalisation of the content in a user defined way.

Adding metadata for common controls pave the way for, and provide in the need and promise of, technology being extremely flexible. In this way the conditions for delivering the expectation that users will be able to optimise their interaction experience according to their personal preferences or accessibility needs of many systems will be secured.

Familiar terms and symbols

What is familiar for some users may not be so for others, requiring them to learn new terms or symbols if they have never seen them before. This may lay such a burden on users that is makes certain content unusable.

Replacing these terms or loading a set of symbols that are appropriate for the specific user ensures that all users find the content simple and familiar. Having familiar terms and symbols is key to being able to use the web and the metadata makes this possible.

Context sensitive help

The same metadata also provide a way for browser extensions to be able to add context sensitive help for common controls or hide controls that the user finds hard to use correctly.

Autocomplete is another example of how knowing what a control is can help the user agent add support.

Note: Purpose of controls may also benefit speech users who rely on accessible names. For requirements related to Accessible Name, refer to Success Criterion 2.4.12.

Benefits

This explains how following the success criterion benefits particular types of users with disabilities.

Following the success criterion benefits users with particular types of, or a combination between, these disabilities in multiple ways:

Language related

Memory related

Focus and attention deficit related

Executive function and decision making related

Examples

Examples in Understanding pages are normally simple lists of hand-waving examples. Sometimes, examples are instead provided in sub-sections with headings. In either case, examples should stay high-level and not get into code specifics, which is for techniques.

When metadata for common input controls is provided:

Example

Resources

Techniques

This section references techniques that can be used to meet the Guideline or Success Criterion. There are sub-sections for sufficient techniques, advisory techniques, and failures.

Remove any parts of the template that are not used, such as the section and heading for situations, sub-lists of techniques, or the "AND" construction. Also remove the square brackets around placeholder optional components.

Sufficient

Techniques that are sufficient to meet the Guideline or Success Criterion.

  • Use semantics to provide extra context (COGA Techniques 4.1). EG: <button coga-action="undo">default</button>
  • Provide semantics that allows for symbols on key content (COGA Techniques 4.2)
  • Using schema semantics
    • <button type="button" itemprop="http://schema.org/SendAction">Send</button>
    • <a rel="next" and rel="prev"></a>
  • Using microformats http://microformats.org
  • Using autocorrect on datafields (conforming to https://www.w3.org/TR/html5/forms.html#attr-fe-autocomplete)
  • Use of aria-invalid and aria-required
  • Use of aria epub on document content
  • Use of aria landmarks with coga context where supported

Advisory

Techniques that are not sufficient by themselves to meet the Guideline or Success Criterion.

Same template as sufficient techniques.

Failure

Techniques that document conditions that would cause the page not to meet the Guideline or Success Criterion, even if sufficient techniques are also used.

Same template as sufficient techniques.