User:Colin/AltGuideline
From Wikipedia, the free encyclopedia
Alternative text is text that serves an equivalent purpose and provides the same essential information as an image in an article, and is intended for text-only users. This should preferably be a short piece of text co-located with the image. If this is not practical, for example because the image presents a lot of information, then a very brief description of the image or overview of the information should be given and a longer text alternative offered elsewhere.[1][2] Absent or unhelpful alternative text is a source of frustration for blind users of the Web.[3]
This is a draft revision of the Wikipedia:Alternative text for images page.
This page in a nutshell: Provide a text alternative for images that serves the same purpose and presents the same contextārelevant information. |
An image that is purely decorative (provides no information and serves only an aesthetic purpose) requires no alternative text. Ideally, such images would be ignored by screen readers and text-only browsers[4] but in practice this is not generally possible on Wikipedia.
A short text alternative is typically implemented on Wikipedia through a combination of the image caption and the image alt
attribute. MediaWiki does not support HTML's longdesc attribute, so any lengthy text alternative must be offered within the article body text. Image wiki-markup should specify the alt
attribute and supply it with carefully chosen text as the MediaWiki-generated alt text is unlikely to be optimal. Blank alt
text is rarely an acceptable choice because nearly all images on Wikipedia are also links, and screen readers will read out a link filename if the HTML alt
attribute is blank or missing.[Note 1] In this regard, Wikipedia must diverge from most alt-text web guidelines, where blank alt
text is recommended for many situations.