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Documents created in a word processor (Word, Google Docs, Pages) create a structure using the built-in heading styles (e.g. Heading 1, Heading 2). That structure will be saved in the native document format, or by saving as a tagged PDF. PDFs created from a scanned document usually do not have outlines because the scanner cannot distinguish between chapters or sections within a document. It can be complex to tag PDF files, and we suggest contacting the accessibility team if you need help.
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