3.20 Provide information to enable users to receive documents according to their preferences

Rationale

Allowing users to choose between different interface options is good practice, as long as the range of options and their meaning is clearly explained up-front.

Users who want to download files such as documents, program executables or multimedia files will want to select versions compatible with their systems. Users are very reluctant to commit to downloading files, especially larger files, if they can't tell whether they will be able to open or use them.

Non-native users may want to select different language options, while users of older technology, text-only browsers or screen readers may prefer to use pages that are optimised for these user agents.

Directions and Techniques

Provide clearly available links to alternative presentations

Whenever alternatives are available provide clear links to the alternatives.

Configure the server to choose document preferences automatically

Browsers can send information about what representations they prefer when they contact the server to request a web page. For example, a browser could indicate that it would like to see information in Irish or English.

Consider using profiles to record user preferences

User preferences for document and page settings can be stored in profiles, so they are automatically served on repeat visits.

Indicate file sizes and file types in links which activate downloads

Providing users with details of the file size and document type in the link title makes it easier to ensure that they are downloading the file which best suits their needs. It is very frustrating to download a document, only to find that it is not compatible with your system or software.

Use the aural property attributes if you use aural style sheets

Aural style sheets specify the presentation of aural content. They can be overridden with user style sheets in the same way as Cascading Style Sheets so users can set the attributes of the aural output to suit their needs, provided they were specified in the original style sheet. See WAI recommended techniques for using aural properties

Use Cascading Style Sheets (CSS) to specify content presentation

CSS specify the presentation of content. They can be overridden with user style sheets. This means that users can set presentation attributes to suit their needs, provided they were specified in the original style sheet. See WAI recommended techniques on specifying content presentation with CSS

Use the CSS2 "media types" attributes

The CSS2 "media types" (used with @media rules) allow authors and users to design style sheets that will cause documents to render more appropriately on certain target devices. See WAI recommended techniques on using media types attributes

How you could check for this:

There are no specific test methods recommended for this guideline.

- View WAI Checkpoint 11.3