The encyclopedia · Product & Design · Product decision · 2007–2011
EPUB won e-books by building an open, reflowable format on web standards
EPUB is a ZIP of XHTML and CSS that no vendor owns, so publishers ship one file every reader can open.
International Digital Publishing Forum · W3C · Sony · Random House · Apple · Google
the move
Early e-readers used vendor formats like Kindle's MOBI, so books bought on one device could not open elsewhere.
The IDPF built EPUB, an open format; its roots date to the 1999 Open eBook Forum, and EPUB 2 was published in 2007.
It packages XHTML, CSS and XML, so it reflows like the web and carries the same openness, and it is free to implement.
Because it was open, Sony, Apple, Google and most retailers adopted it as the common format, leaving Amazon's MOBI the outlier.
why it works
- EPUB gives publishers one file that works across devices and apps.
- It is built on XHTML and CSS, so it reflows like web pages and is easy to make.
- It is open and free, so no vendor can use it as lock-in.
- Sony, Apple and Google chose it as a common standard over rival formats.
what transfers
When incumbents lock users in with a proprietary format, the counter-move is an open standard built on technologies developers already know.
what came after
EPUB became the de facto open e-book standard (EPUB 3 in 2011), and W3C took over its stewardship, though Amazon's Kindle still uses a side format.
references
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