How EPUB Compares to Other File Types and how to Build One
The tablet and electronic reader (such as Amazon’s Kindle reader, the Apple iPad, and others) truly revolutionized global book publishing as they brought down the cost and the risk of a new book to unprecedented lows, and with them came the EPUB file type. EPUB (electronic publishing) is the predominant format now when it comes to releasing new books as most online bookstores offer it. However, online publishers should be completely familiar with the pros and cons of EPUB when compared to other types, namely Microsoft Word and Adobe PDF.
Portable Document Format (PDF) is ubiquitous in the desktop and laptop world because it ensures that the formatted document stays the same, whereas the formatting of Word files depends on the program version being used. Furthermore, PDFs can be easily produced using most Office Suites. Thus, PDFs are seen as the most trustworthy type of document because of the difficulty associated with altering them. Unfortunately, this same difficulty makes viewing PDF files on portable devices unpleasant and sometimes impossible, as they cannot be adjusted to fit the device’s specifics. For example, Amazon’s Kindle Fire has an awful zoom feature that makes reading a whole PDF book a real challenge.
In comparison, EPUBs are specifically tailored to portable devices and make full use of the limited functionality. For example, the text doesn’t go on without distinct markings (as with Word and PDF files) but is divided into separate sections easily accessible from the contents menu. EPUBs are made using XML and XHTML so they can be read by most types of software and do not require heavy processing power. The major drawback to EPUBs is that they require specialist knowledge and preparation to produce, and aren’t something that can be done with a few clicks (as with PDFs).
Quite a few online books are written in HTML using the CSS styling, and this can be very useful when creating an EPUB file. The only difference is that it needs to be in XHTML, which has further requirements like closing elements, quoting around attributes and more. Thankfully there are a number of free converters on the Internet1. For the best visibility, divide the whole text into chapters and place each in a distinct file. These should be saved in a dedicated folder to avoid confusion.
Every EPUB needs its “mimetype” file, which is really a text file with the content: “application/epub+zip” and saved without an extension. Two other layout files are needed as well; the page and book styles. They should be called page_style.css and stylesheet.css and their text should read:
Naturally, you will want a cover image so try to choose a JPG file smaller than 64KB. Do take into account that some readers have a black and white screen, so it’s important to consider how the image will look on it. The image is very important when marketing the book so consider having a custom one designed.
Having done all of this, you should build 1) The title page, 2) The table of contents, 3) the container XML file and 4) the contents list. Everything except 3) goes to the same directory as the other files, while the container XML file should be saved in a META-INF sub-folder. Be aware that additional information, such as the author’s name, date, genre, etc., should be located in the contents list file (the content.opf). Having created all files, use a zip program, but instead of using the extension .zip, write .epub. Ignore any protests from the operating system.
These steps should create a functioning EPUB file. However, always check whether the conversion is successful.