Accessibility - Guidelines on alt texts in img elements

Summary:

In HTML authoring, there are very good reasons to include an 'alt' attribute into every 'img' element. The purpose is to specify a textual replacement for the image, to be displayed or otherwise used in place of the image. Thus, the prime rule is: Consider what the page looks like or sounds like when images are not shown. Then, write for each image an 'alt' text that best works as a replacement. This document also gives more specific suggestions for simple, common situations, and some uncommon too. For content-rich images, it recommends explicit links to textual alternatives.

Originally written probably 1998-09, with the title Simple guidelines on using ALT texts in IMG elements.
This page belongs to section Web authoring and surfing of the free information site IT and communication by Jukka "Yucca" Korpela.