ALT Tags

ISSUE:

Images cannot be directly accessed by users of screen-readers, foreign language translation applications or some hand-held devices. Similarly, some users choose to disable picture loading — especially those users with slower dial-in connections.

An ALT tag is used to specify alternative text for an image. The alternative text will be spoken by a screen-reader, provide target text for users of speech-recognition technology, be displayed by browsers with picture loading disabled, and displayed briefly when a mouse or other pointing device is placed on the graphic. In the absence of an ALT tag, an unidentified gray box will be displayed by graphical browsers with picture loading disabled and screen-readers will speak the path and file name for the graphic — this rarely provides any useful information.

STANDARD:

• Include alternative text for all graphics.



• Do not use acronyms and abbreviations in the alternative text for Images or other non-text elements.

EXAMPLE:

The following HTML code is used to display the image of an upward-pointing arrow by graphical browsers with image-loading enabled. The text "Up Arrow" will be spoken by a screen-reader and visibly displayed in place of the image by a text-only browser or a graphics-capable browser with image-loading disabled.

<img src="../Graphics/uparrow.gif" height="27" width="27" border="0" alt="Up Arrow">