EPUB is the distribution and interchange format standard for digital publications and documents based on Web Standards. EPUB defines a means of representing, packaging, and encoding structured and semantically enhanced Web content for distribution
in a single-file format. EPUB allows publishers to produce and send a single digital publication file through distribution and offers consumers interoperability between software/hardware for unencrypted reflowable digital books and other publications. EPUB
3.1 will be released by the end of the calendar year.
Accessibility has always been of great importance to the IDPF. This accessibility documentation represents a basis for accessibility evaluation and discovery of accessibility qualities for any version of EPUB (past, present, or future).
These documents define categories of accessible EPUB:
Discovery-only — this category of EPUB Publication meets the discovery metadata requirements of this specification, but does not meet the accessibility requirements. Conformance is defined in
Discovery-Enabled EPUB Publications.