PDF (.pdf) is simply a file type, just like .txt, .xlsx, or .docx. PDF stands for Portable Document Format.
PDF files typically start as another document type, such as a Microsoft Word document, and are then exported or saved as a PDF. There are then two files containing the same content - a Word document (.docx) and a PDF (.pdf). Many files found on the web are PDFs. They are used for many reasons:
PDF files typically start as another document type, such as a Microsoft Word document, and are then exported as PDFs. Ideally, document accessibility should begin there. Many things can be done to support accessibility in the source file, such as adding alternative text for images; defining structural headings, lists, and data tables; and providing a document language.
Create Accessible PDFs (Microsoft)
Learn how to use Microsoft Office to create documents that can be saved as a more accessible PDF.
Whether or not you have access to a source file, Adobe Acrobat can be used to assist with PDF accessibility.
PDF Accessibility Overview
Learn the characteristics of accessible PDF files, such as searchable text, navigational aids, and a proper title.
Acrobat Pro Accessibility Checker
User Acrobat's built-in checker, which provides a guided, step-by-step approach to fix accessibility issues.
Create and Verify PDF Accessibility
Learn the Acrobat tools that make it easy to create accessible PDFs and check the accessibility of existing PDFs.