When people talk about "accessible" PDF files, they are usually referring to "tagged" PDF files. PDF tags provide a hidden, structured representation of the PDF content that is presented to screen readers. They exist for accessibility purposes only and have no visible effect on the PDF file. There is more to an accessible PDF file than tags, but an untagged PDF would not be considered "accessible".
HTML tags and PDF tags often use similar tag names (e.g., both have tags named h1) and organization structures. If you are comfortable with HTML, you will probably have an easier time creating and editing tagged PDF files, but knowledge of HTML is not necessary.
Adobe, Acrobat, and PDF
Adobe, Acrobat, and PDF are often used interchangeably, but they are not the same. The relationship between these terms is similar to the relationship between Microsoft, Word, and DOC(X).
There are 3 Acrobat Tools:
- Acrobat Reader allows users to view and interact with a PDF (including the accessibility features of a PDF), but it cannot be used to create new PDFs or edit existing ones.
- Acrobat Standard adds the ability to create a PDF, along with other features like converting a scanned PDF to a searchable file. However, you cannot view or edit accessibility information.
- Acrobat Pro is the only version of Acrobat that can be used to view and edit the accessibility information of a PDF.
There are other programs that can be used to view, create, and edit tagged PDFs, but we will focus on Acrobat in this article