The new 3.0 standard has 4 defining documents with new names. The OPS referenced a DAISY standard for the NCX file. In version 2.01 there were three defining documents, the OPF (Open Packaging Format), the OCF (Open Container Format), and the OPS (Open Publications Structure). The informational documents are also quite useful in understanding the standard's intent and content.Īn alternative XML syntax called DTBook was available as an option in this version, but this was removed in EPUB 3.ĮPub version 3 is the newest version of the standard and has now been recommended by the idpf standards committee. In particular check the version 2.01 OPS and OPF specifications and the version 1.01 OCF specifications. The IDPF specification page contains the specifications for this format. This is currently the main format used by the Amazon Kindle, replacing earlier use of MOBI or its variant AZW / AZW3.

An ePub reader should be capable of reading the content in its compressed format. It has special requirements by including an uncompressed mime type file while the rest of the data in the file is compressed. This container is generally a zip file but the extension has been renamed to. For this reason the files are collected into a container for easy dissemination and use. The intent of ePub is to serve both as a source file format and an end user format. The Open eBook Publication Structure or 'OEB', originally produced in 1999, is the precursor to OPS. '.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' is composed of three open standards, the Open Publication Structure (OPS), Open Packaging Format (OPF) and Open Container Format (OCF), produced by the IDPF. '.epub' is the file extension of an XML format for reflowable digital books and publications. It is based on XHTML and XML along with optional CSS stylesheets. 4 Digital Rights Management & EncryptionĮPub is an open format defined by the Open eBook Forum of the International Digital Publishing Forum ( IDPF).

Calibre epub reader wiki