If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following:
The purpose of this success criterion is to ensure that users can change the font of all text to better suit their reading needs.
At this level, some exceptions are made so that authors can use images of text where essential to the presentation. Success criterion 1.4.9 serves the same purpose but does not allow any exceptions.
How to Meet
Authors must ensure that they do not use images to style the text of a publication in a specific way when fonts and CSS can accomplish the same outcome.
It is permissible to use images of text under this success criterion when the presentation is necessary and, for example, fonts cannot be embedded or styling cannot be ensured. Authors should weigh how critical the presentation is compared with the problems this may cause for readers.
Note that incidental text in the background of an image is not subject to this requirement (e.g., signs and building names in a cityscape).
The following knowledge base pages provide more information about how to address this success criterion for publishing content: