The following WebAIM articles outline how to make your files more accessible on the web
Microsoft Word is currently the most widely-used word processor on the market. Because it is so common, the .doc format has become the de facto format for text documents. MS Word is often used to create PDF and HTML files for websites. Despite some gains in recent years, creating accessible web content with Word is NOT a straightforward process.
When people talk about "accessible" PDF files, they usually are referring to "tagged" PDF files, even though there is more to an accessible PDF than tags. PDF tags provide a hidden structured, textual 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.
Microsoft PowerPoint is one of the most popular tools for creating slide show presentations. It is often used to organize thoughts for a meeting or lesson, to present key points in a live presentation, and even to create handouts.