What is Electronic Publication (EPUB)?

Dive into the most popular file format for digital books in the world… EPUB.

epub read on e reader
Photo by Perfecto Capucine on Unsplash

Due to the global pandemic, we are facing the at-home alternative of almost everything. Now that everything has to be—or at least be able to be—done at home, creators are required to familiarize themselves with the digital alternative of their works.

We know that the digital versions of books are already available before, but with what’s going on today, the urgency of book designers to get a hold of electronic publishing (EPUB) increases greatly.

Electronic publishing was first popularized by Project Gutenberg, a volunteer effort aiming at encouraging the creation and distribution of eBooks. This project is the oldest digital library that was founded in 1971 by American writer Michael S. Hart. It collects many books, with the majority being full texts of books in the public domain.

If you work in the publishing domain, you may already start entering the worlds of digital publishing in addition to prints only. Compared to printed publications, digital publications will allow you to make a bigger distribution amid limited physical mobilization.

This is a great opportunity for book designers to delve deeper into e-book designs because companies and organizations are in dire need to switch to digital if they want to keep thriving. Now, before we dive into EPUB more technically, let’s get to know more about digital publishing.

What is Digital Publishing?

Lahle Wolfe’s definition of electronic publishing or digital publishing is taking anything that could be done in print, sound, or that can be seen with the eyes and putting it into a format that can be accessed by computer technology. Therefore, we are not only talking about books, but we must also be familiar with the following items.

  • Newsletters
  • Journals and blogs
  • Advertisements
  • Company Reports
  • Catalogues
  • Magazines
  • Scrapbooks

As you can see, there are many items that can be designed to be delivered digitally. While the others simply come in the digital version of themselves, books may come in different forms. Among other types, EPUB is the leading e-book file format because many e-readers support this format and compatible software is available for most computers and mobile devices.

What is EPUB?

EPUB (short for Electronic Publishing) is one of several ebook formats that are available today. This format is special because it’s free to use, vendor-independent format, which now has grown to become the most common format in digital publishing.

EPUB 3.2, which is the latest EPUB version, has built-in support for embedded interactivity, audio, and video. This is why EPUBs are even more interesting; instead of going electronic because it’s more affordable and more portable, e-books will actually do something that printed books cannot do, which is displaying multimedia. Book writers and designers now have the chance to further explore their means of delivering information, which makes the information easier to access and more likely to deliver successfully.

Other Popular Formats

EPUB, MOBI, AZW and AZW3, IBA, and PDF are some of the more popular digital publishing formats in the digital publishing world, but there are also the following formats.

  • LRS, LRF, and LRX for the Broad Band e-book format
  • FB2, the XML-based started in Russia
  • DJVU, which is pretty cool because it can store more than 100 black and white scans in less than a megabyte
  • LIT, a Microsoft’s proprietary e-book format, which now has been discontinued
  • RFT, also known as Rich Text Format

This may be overwhelming for starters, but really, if you are thinking about creating e-books, focusing on three formats would suffice. EPUB, MOBI, and AZW is more than enough, but then again EPUB only is a great option.

Why EPUB is a Great Option

It’s fair to assume that PDF is very widely known and is more commonly used, especially to handle abundant image content. However, for longer books, EPUB is a great option because it’s more relevant and easy to use.

EPUB allows users to adjust their viewing preferences, like changing font sizes, font types, etc. It is also designed to be responsive, where the content will adjust to the device layout. The content in an EPUB document will re-flow according to the screen size, so users can still read comfortably. In comparison, PDF doesn’t have the ability to be responsive. When you access a PDF document on a device with a smaller screen, you would have to zoom in, pan, and pinch in order to read the document.

In addition to that, EPUB files are easier to edit. You just have to make changes in the HTML codes and you can make whatever modifications you need. With PDF, you need certain software in order to edit and make changes to the content and layout.

There are many other considerations that make us choose EPUB over PDF. However, one of the biggest reasons why EPUB is more favourable is when you want to sell ebooks. If you have PDF files, you have to convert them to EPUB to have them sold in e-book distributors such as Amazon, Apple, Nook, Kobo, etc.

How to Create EPUB

There are several ways to create EPUBs, but if you have one or more reasons below, then Adobe InDesign is your best friend.

  • You want your e-book to look good in all kinds of device
  • Your book has complex design elements (tables, lots of images, sidebars, endnotes, drop capitals, etc.)
  • You want to add a read-aloud track, video, or other enhancements
  • Your book contains non-Latin characters
  • You have complex chapter headers
  • The idea of looking at HTML makes you break out in hives

Everything that might sound intimidating when creating EPUB, they can be made easy by Adobe InDesign. Again, not only books, InDesign is also great to create posters, flyers, brochures, magazines, newspapers, presentations, and more! Yes, including those files with generally more complex layout compared to books.

Side note, you are welcome to drop me an email if you have more questions on EPUB, InDesign or digital book design in general.


  • EPUB/PDF and other digital formats are a big opportunity for creators to expand into more interactive publication product
  • Even though printed books will not end anytime soon and its users will always be here, the digital version of books will still be in high demand, and ever-increasing
  • Designers and creators should understand the difference between PDFs and EPUBs so that they can decide which one works best for what they need

Want to learn more about digital book design? Join our hands-on training on how to optimize the new and improved Adobe InDesign! This training is in collaboration with Adobe and can be streamed from the comfort of your home. More importantly, it’s FREE!