EPUB 3.2
The EPUB® specification is a distribution and interchange format standard for digital publications and documents. EPUB defines a means of representing, packaging and encoding structured and semantically enhanced Web content — including HTML5, CSS, SVG, images, and other resources — for distribution in a single-file format.
EPUB 3, the third major release of the standard, consists of a set of four specifications, each defining an important component of an overall EPUB Publication: