2.3.2. HTML 4.0 Guidelines for Mobile Access

By Rainer Hillebrand

The "HTML 4.0 Guidelines for Mobile Access" ( http://www.w3.org/TR/NOTE-html40-mobile/) are a W3C Note for discussion, published on March 15th, 1999. This document isn't a reference material. It "describes guidelines for content authors how to create HTML 4.0 contents to be acceptable to mobile devices as much as possible." [2]

Markup language

HTML 4.0 Strict, which excludes the presentation attributes and elements.

Styles

External style sheets (CSS).
Use the 'media' attribute in the 'style' or 'link' element so that user agents can select appropriate style sheets.
Inline style sheets via the 'style' attribute are not preferred.
Web pages should be readable without style sheets.

Scripts, event handlers

Web pages should be readable even if scripts are not executed.

Forms

Some features, which depend on local file systems, such as file upload, should not be used.
'type="image"' in the INPUT element should not be used.
You should not rely on scripting, and should avoid using attributes for event handling, such as onsubmit.

Frames

Frames are not part of HTML 4.0 Strict. Therefore, frames should not be used.
If you can't or don't want to avoid frames then apply to the following guidelines:
- "Provide a fallback content for contents that contain frames using NOFRAMES at the end of each FRAMESET." [2]
- "Name each frame via the 'title' attribute on FRAME elements so that users can keep track of frames by name." [2]

Image maps

Server-side image maps should not be used.
If client-side image maps are used then provide alternative descriptions via the 'alt' attribute of the AREA element.

Tables

It would be safe to avoid using tables whenever possible.

Objects and images

"When embedding objects via OBJECT element, alternative contents should be provided by the fallback mechanism of OBJECT element. These alternative contents should end up with texts." [2]
"In general, images should be embedded via OBJECT element, as it has better fallback mechanism, but IMG element may also be used. In this case, alternative description via 'alt' attribute [...] should be provided for user agents which cannot or do not render images." [2]
"If the image represents an important information, a long description should be provided via longdesc attribute of IMG element, in addition to alternative text via alt attribute." [2]
"The APPLET element, which is not part of the HTML 4.0 Strict, should not be used in favor of the OBJECT element." [2]

Access keys

The assignment of access keys via the 'accesskey' attribute for the elements A, AREA, BUTTON, INPUT, LABEL, LEGEND and TEXTAREA will be effective if it is supported.
You should not rely on access keys for navigation.