This guide takes a slightly different approach to accessibility because of the feature-rich nature of EPUB 3. Instead of grouping all the practices together under a single rubric of essentiality, I’m going to instead take a two-tier approach to making your content accessible.
This first section deals with the core text and image EPUB basics, while the second ventures into the wilder areas, like scripting and the new accessible superstructures you can build on top.
I’m going to start with a section on the fundamentals of accessible content, naturally enough, because if you get your foundation wrong, everything else degrades along with it.