programmatically determined text that is used in place of non-text content, or text that is used in addition to non-text content and referred to from the programmatically determined text. [It seems that there should be a clearer way to say this… Or perhaps better, give a couple of examples.. This is so fundamental, one wants it to be absolutely clear.]
Relation to non-text content Referred to from
1. Used in place of 1. [Is this information missing from def?]
2. Used in addition to 2. programmatically determined text
We have included an example to make this clear.
Example: An image of a chart is described in text in the paragraph after the chart. The short text-alternative for the chart indicates that a description follows.