Definition
Reading order
The sequence assistive technology reads a document's content — defined by the tag structure, not the visual layout. Untagged PDFs expose raw drawing order, which is why they read scrambled.
A page's internal drawing order can be anything the generating software emitted; columns interleave and footers interrupt sentences when a screen reader follows it. Correct reading order is encoded as the order of structure elements in the tag tree — rebuilding it is a core remediation task.
Related tools & guides
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