STEM publishing requires precision; the content’s visual appearance must precisely and reliably reflect the author’s intention. Historically, this concern was limited simply to the content’s visual appearance. To ensure equal access to users with disabilities, today it’s vital to ensure that similar precision is applied to alternative representations and usage of the content.
As an additional benefit, well-tagged PDF is optimized for reuse by software capable of directly leveraging the author’s intent as expressed via PDF’s tag tree.
These pages demonstrate LaTeX to accessible PDF conversion:
There are many different routes by which Assistive Technology (AT) can read STEM documents. Not all are successful at conveying the author’s intent. For discussion of other ways of conveying the author’s intent, some good and some less good, this page presents examples of various technologies’ vocalization of a PDF file containing STEM content, including MathML.