An Expansive View of EPUB at the Frankfurt CONTEC Conference

October 22, 2014

The message about EPUB at the Contec Conference at the 2014 Frankfurt Book Fair was expansive:

  • new directions in which EPUB is expanding;
  • new domains EPUB is addressing;
  • and an expanding global reach.


“EPUB 3 Now”

IDPF was asked to put on a session on “EPUB 3 Now” in the Supply Chain track programmed by EDItEUR, the international organization responsible for many important standards such as ONIX, Thema, and others. Bill McCoy, IDPF’s Executive Director, served as moderator and provided background; I was recruited to talk about the EDUPUB initiative; and Len Vlahos, Executive Director of our partner organization BISG, talked about and demonstrated the innovative resource that is a collaboration between the IDPF, BISG, and DAISY.

That selection of speakers and topics in itself is indicative of the broad reach of EPUB throughout the publishing ecosystem.

It’s Global. Now.

Bill McCoy opened by pointing out that IDPF now has over 350 member organizations from 45 countries. The distribution may surprise you: only 40% are from North America, closely followed by 34% from Asia; 21% from Europe; and 5% from the rest of the world. Clearly, establishing EPUB as a global standard is no longer just a goal—it’s a reality.

EPUB 3 is being particularly holistically adopted in Japan, Taiwan, and Korea; major international publishers like Hachette, Elsevier, and O’Reilly have standardized on it. And EPUB 3.0 has recently been approved as an ISO Technical Specification, which will make it easier for other organizations and countries to officially adopt it. (South Korea already has: it’s a Korean National Standard.)

EPUB Systems and Tools are Proliferating

Reading system support is increasing rapidly, from such diverse companies as Apple, Google, Kobo, Adobe, VitalSource, TXTR, Sony, Tokyo Shoseki, Shogakukan, ACCESS, Voyager Japan, and Mantano.

Authoring tools are coming along as well, with recent advances in mainstream tools like Adobe InDesign, Apple Pages, and Ichitaro as well as in specialized tools like Aerbook, Metrodigi’s Chaucer, and Aquafadas.

The EPUB Spec is Evolving Rapidly . . .

Bill announced that the IDPF plans to release EPUB 3.1 during 2015. The Working Group is just getting set up (IDPF members: join!), and there’s an ambitious but very achievable agenda for this next release.

First of all, it will integrate many of the enhancements that have come out of the EDUPUB initiative (more on that below) such as new specifications for Widgets and Distributable Objects, plus other specs nearing completion such as Multiple Renditions, Indexes, and Dictionaries and Glossaries.

EPUB 3.1 is expected to also focus on better support for other vertical markets, such as comics, magazines, scientific and scholarly content, and corporate documents. In keeping with our commitment to web standards, it will continue to improve alignment with the Open Web Platform, perhaps including HTML serialization. Discussions are ongoing with the W3C on how EPUB can best evolve in the long term to provide seamless online and offline experiences.

. . . but It’s Not Just About the Spec Anymore.

New this year is a shift in IDPF philosophy toward emphasis on a holistic EPUB Platform. That means instead of just crafting a “pristine spec,” and then sitting back and waiting for it to be implemented, the IDPF will make implementation support an integral part of the adoption of any new spec. This is much more likely to result in a spec that has a practical impact, and that can be demonstrated to have realistic near-term chances of real-world implementation.

Readium is obviously key in this regard. Originally a proof-of-concept implementation of EPUB 3 in JavaScript packaged as a Chrome Extension, it has rapidly evolved to become an indispensable resource, based on the Mozilla/Apache/OpenStack model for promoting an open ecosystem via open source software. The Readium Foundation now has 47 members from around the world, working aggressively on Readium SDK (14 vendors are already shipping apps based on it!); Readium JS, a rendering engine for cloud and browser-stack apps; and Readium LCP, a lightweight technology for rights management first implemented by Learning Ally.

The EDUPUB Alliance

Another great example of the expansiveness of EPUB is the EDUPUB Alliance, which brings together a number of organizations and related standards to build an agile, open, interoperable ecosystem for education globally.

This is a collaboration between, originally, the IDPF (providing the basis for the distribution and interchange of educational content via EPUB); IMS Global, which governs key educational standards like QTI (Question and Test Interoperability), LTI (Learning Tools Interoperability) and the Caliper Analytics Framework; and the W3C, which provides the Open Web Platform on which so much of this is based. BISG has also recently joined the EDUPUB Alliance, forming a Working Group charged with helping to publicize and educate the publishing community about EDUPUB.

The EDUPUB Profile of EPUB 3

One of the primary outcomes of this initiative is IDPF’s development of the EDUPUB Profile of EPUB. The EPUB 3 Working Group has been working diligently on this all year; a second Working Draft is available now, and the plan is to have a complete implementable spec finalized by the end of the year.

It’s important to realize that EDUPUB is not a new, separate standard; rather, it’s a specification of how to create an EPUB optimized for education. The resulting file is still an authentic EPUB 3 file, .epub. But in conforming to the EDUPUB spec, that EPUB file will have features that are particularly useful for learning, teaching, and integrating into Learning Management Systems.

For example, it will clearly distinguish a teacher edition from a student edition of a textbook, and it requires stricter use of HTML5’s <section> structure and headings (as well as page break markers when there is a corresponding print or paginated rendition) to make it more accessible and easier to use in the classroom.

New Features for EPUB 3 in General

EDUPUB has also contributed a host of useful additions to the EPUB Structural Semantics vocabulary, addressing the need for terms pertaining to testing, learning objectives, and other structures that come up in educational contexts.

A number of aspects of EDUPUB have actually prompted or accelerated specs that are now part of EPUB in general. For example, the work on Widgets was accelerated due to EDUPUB, and the need for Distributable Objects (extracting chunks of content from an EDUPUB for separate distribution) has become a draft EPUB spec. The Multiple Renditions spec from the Advanced Hybrid Layout WG and the work done by the Annotations WG will be very valuable for EDUPUB. And IMS Global has published a Best Practices document for using Caliper Analytics, QTI, and LTI with EPUB 3.

The EPUB Support Grid—

Wrapping up the session, Len Vlahos from BISG demonstrated the latest incarnation of the EPUB Support Grid, a collaborative resource from the IDPF, BISG, and DAISY.

Originally a simple spreadsheet showing which features of the EPUB 3 spec were implemented on various reading systems, it is now a sophisticated online resource that is full of rich information about the rapid advance of EPUB 3 adoption among reading systems.

It provides a set of especially programmed files that systematically test individual features of EPUB 3 and report the success or failure of a given reading system to implement them. This is freely available at; reading systems use this all the time to test whether their systems are keeping pace, and whether new features are working properly. Thus the Grid not only reports on reading system compliance, it actually helps foster it!

A Ready Reference, Continually Updated

In addition, the members of the BISG Content Structure Committee are responsible for systematically testing reading systems and reporting the results on That means you can just click on and see what features a given reading system has successfully implemented. Or, you can select certain features and compare the results across all the reading systems that have been tested. This is ongoing work that is continually expanding, providing much more up-to-date information to the publishing community.

And Now Assessing Accessibility

The latest addition to is a suite of tests for accessibility. These have been developed by DAISY to ascertain how the various reading systems, often paired with specific assistive technologies like screen readers, perform for those who have print disabilities. These tests are actively underway; BISG expects to formally announce this support for accessibility on by the end of the year.