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.

  • 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.

  • 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 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.

  • 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.

Copyright © 2001-2003 by Rainer Hillebrand and Thomas Wierlemann