The electronic book comes in many different formats, from EPUB to PDF to Kindle’s MOBI and many others. You may not know that not all EPUBS are alike.
EPUB is an e-book file format that uses the .epub file extension. EPUB ebooks automatically adjust to fit your screen. You can change display options like the font size, number of columns, and more. EPUB is a technical standard published by the International Digital Publishing Forum (IDPF) adopted in 2007. But even within this standard, there are two types of EPUB ebooks: Adobe and Open EPUB.
Adobe EPUB ebooks are protected by Adobe’s Digital Rights Management (DRM) system of copy-protection. You’ll need to authorize your computer or device before you can read protected EPUB files.
Open EPUB ebooks have no DRM protection. There’s no tracking or authorising involved, just download an Open EPUB and read it. Open EPUBs can be downloaded to any reading app like iBooks or Google Play Books.
On Windows, Microsoft’s Edge browser includes a basic EPUB reader, but you can get extensions for Chrome and Firefox browsers as well. Calibre is probably a better solution as a fully-featured ebook library manager and reader. On Mac, the iBooks app is the primary tool under iOS. Google Play Books is the go-to EPUB reader on Adroid phones and tablets. You can’t read native EPUB files on Kindles, they have to be converted to the .mobi format before being loaded onto a Kindle reader.
You could also convert an EPUB to a PDF which can be read through Adobe Reader, or any PDF reader such as Foxit or Evince. It is worth pointing out that Adobe Reader will only open PDF documents. It will not open native EPUB files. You could use Adobe Digital Editions (ADE) to read EPUBs, which is available to download for free on both Mac and Windows systems.
Standards or no
You can see from all this that the EPUB is far from standard as standards go, with competing formats, services and readers all trying to assert dominance over the ebook market. PDF may have been the pioneer of portable documents, but the specifications of the long-established format make it difficult to deliver a good e-reading experience. So we have all these other options, making the ebook publishing process far from simple.
Unusually, no one supplier has managed to corner the market to become the dominant player and de facto standard. While many competitors have fallen away of consolidated into one of the remaining formats, the electronic publishing business remains as divided as ever.