You will notice that open textbooks are available in a number of different technical formats, some of which may not be familiar to you. The reason for this is because research into student preferences around textbook formats shows that students want flexibility. You may have students who prefer physical textbooks, while others will want their textbook delivered to their favourite eReader software. Still others prefer the familiarity of PDF or a website.
Here is a brief guide to the different, common types of open textbooks document formats.
PDF is a common file format that requires a PDF reader. It lacks the text reflowing capabilities of ePub. Free PDF readers include Adobe Reader, Foxit, and Nitro. PDF is a good format to distribute a textbook to students in as it is common and most students will know how to work with a PDF document. However, if you have created a textbook and make it available for other instructors to modify as they see fit, you should also make your source files available for editing purposes as PDF files are very difficult to edit.
ePub is a standard format for ebooks. You will need an eReader to read ePub files. eReaders are available as stand alone devices (such as a Nook or Kobo reader) and as software packages that you can install on your PC, Mac, tablet or mobile phone.
There are a number of eReaders available for free, and many have features such as cloud syncing, which allows you to read your book on a tablet, PC and phone and keep the book in sync. Many also offer annotation and note-taking capabilities.
ePub is superior to PDF in that the text in ePub readers can reflow based on the size of the device you are reading on, giving you a smooth side to side reading experience. You can also resize the text.
Use ePub if you have a Nook, Kobo or other dedicated eReading device or have downloaded and installed eReader software on your tablet, PC, or mobile device. Note that Kindle does not support ePub. Instead you will want to use the .mobi format (see below).
Recommended free eReader software & devices compatible with ePub
Available as eReader device?
|Adobe Digital Editions||PC, Mac, Android, iOS||No. Software only||No|
|Kobo||PC, Mac, Android, iOS||Yes||Yes|
|Google Play Books||Android, iOS||No||Yes – Google account|
|Bluefire||PC, Android, iOS||No||Yes|
These are just a few of the many ePub readers available. Wikipedia has an extensive comparison list of eReaders.
Students should choose the MOBI format if they have an Amazon Kindle or use the Amazon Kindle software. You do not need to have a Kindle device to use the Kindle software. Kindle apps and software are available for download on Mac, PC, Android, BlackBerry, Windows OS and iOS.
An HTML website is a good format to use to distribute your textbook to students as it is a universal format that does not require any additional software beyond a web browser. HTML is also a good format to distribute your textbook in if you want others to be able to edit or customize your book. If possible, you can create a zip file of your HTML documents and make those available for other instructors to download, edit and host on their own websites.
Some open textbooks are available as Word/OpenOffice documents. These file formats will be have the .docx or .odt file extensions. You will need Microsoft Word or OpenOffice to view these files. Word/OpenOffice documents can be used to distribute a textbook to students as it is a common file format. However, it is more common that you would convert the Word/OpenOffice document to PDF, ePub or HTML for distribution to students and provide Word/OpenOffice as a source file for others who may want to edit or adapt the textbook.
LaTeX is a document format often used when complex scientific or mathematical equations and notations are required. LaTeX requires special software to read and edit. These files are not recommended for students, and are primarily provided as source files for instructors who wish to modify or customize a textbook.