In PowerPoint, it is possible to insert an automatically generated header or footer with slide number, date, and time as well as text on the slides.
As headers and footers are repeated on every slide, this information tends to disrupt the reading flow for users of Assistive Technologies.
Therefore, the header and footer elements on all slides should be marked as decorative so that they are not read by assistive technologies. As of axesSlide version 1.1, headers and footers are automatically artifacted during PDF export if they were created using the corresponding PowerPoint functions. This means that you no longer have to manually mark headers and footers as decorative. You can read more about this topic under Add Alt Text or Mark Object as Decorative.
Note: If the header or footer of your presentation contains important information for all users, such as the date of the presentation, repeat this in another text field on your slide.