From eBooks, filetype, and DRM by Jason Griffey:
“…There are two different things going on when someone tries to open an eBook file on an eReader. One is filetype…how the file itself is organized internally, how the information contained within is encoded. This is analogous to the difference between a Word file saved as a .doc file, a Word file saved as a .docx file, and an Powerpoint file (.ppt). All are different filetypes…the program involved in the creation, editing, and display of those files describes the information contained inside. Right now, there are two main filetypes being used to describe eBook files: the Amazon eBook standard, or .amz file, and the ePub file (.epub) that is used by just about every other eBook vendor.
Amazon purchased Mobipocket (an early ebook vendor/distributor) way back in 2005, and used their format as the basis for their current proprietary .amz filetype. ePub, on the other hand, is an open, XML based eBook standard, and is used by a huge number of eBook vendors…indeed, it’s easily the standard for current ebook publishing.
But filetype is only half the battle. In addition to the way the file is organized/structured internally, there is also Digital Rights Management to deal with. Think of DRM on an eBook as a lock, with your eReader having the key to open the lock and display the file. Without the lock, the eReader can’t open the file at all…can’t even see what it is. And if it has the key, but can’t read the filetype, that’s no good either…in that case, you can view the contents of the file, but will have no idea how to render it on the screen properly.
Amazon, in addition to using a proprietary filetype, also uses a proprietary DRM mechanism. This means in order to read an Amazon-purchased eBook, you have to have an eReader with the right key, as well as the right interpreter for the file. So far, that means that you have to be using a Kindle, or alternatively, using the Kindle software provided for any number of other devices (Windows, Mac, iOS devices, Android devices). This doesn’t mean that’s the way it has to be. Amazon could choose, tomorrow, to remove all DRM from their files. This would mean that you’d still need a program to interpret the .amz, but you wouldn’t need the key anymore. Conversely, Amazon could license their DRM to other eReaders, in effect handing them the key…but it would still be up to the eReader itself to be able to display the .amz file.
Vendors that use the ePub format have chosen different sorts of DRM to lock up their content. Apple and their iBook app use the ePub format, but wrap it up with their Apple-specific Fairplay DRM. This means that while the file itself would be readable by any device that can interpret an .epub file, without that particular key on their keyring, the eReader can’t do anything. Sony, Barnes & Noble, Overdrive, and other eBook vendors have chosen a shared DRM solution. They license their DRM from Adobe, and run Adobe Content servers that provide the keys to epub files that they sell. This means that if an eReader has the key to one of those stores, it has the key to all of them…think of it as a shared master key for any Adobe DRM’d file.
This illustrates why, although both Apple and B&N use epub as their filetype, you can’t buy a book from the B&N store and then move it over to your iBook app on your iPad. Conversely, you can’t buy something on the iBook store, and then move it to your Nook. Same filetype, different lock.
Overdrive, in supporting Adobe DRM’d epub files, work with Sony eReaders as well as the B&N Nook…same filetype, same DRM key to unlock them.
With all that said: any eReader that will read a given filetype will read said filetype if the file doesn’t have any DRM. So if you convert an existing document to an epub using software like Calibre, Sigil, or InDesign, that file will able to be read on a Nook, Sony Reader, AND the Apple iPad/iPhone/iPod Touch. If you have some text and you convert it to, say, a Mobipocket file (.mobi or .pdb) then it would be readable on the Kindle AND the Apple iBooks app…but not on the Nook. For a complete list of eReaders and their corresponding filetypes, there is no better place than Wikipedia’s Comparison of eBook Formats article.
While a DRM free eBook ecosystem would clearly be the best for the consumer (choice of device, free movement of files from device to device, etc), the second best option is an ecosystem where the DRM is ubiquitous and the patron doesn’t even realize it’s there. This was the case with Apple and the early battles for music sales on the ‘net…they had the store and the distribution network (iTunes) as well as the device used to access the content (iPod). All of the content was, originally, DRM’d, but largely no one noticed since it was completely invisible for the average user…”
‘Why isn’t the Kindle compatible?’
The short answer is that the Kindle does not currently support the Digital Rights Management (DRM) protection our publishers and suppliers require for Adobe EPUB and PDF eBooks offered through the OverDrive service…
So, let’s focus on what devices are compatible with Adobe EPUB and PDF eBooks offered through your ‘Virtual Branch’ website. For the most up-to-date list, always direct your patrons to the OverDrive Device Resource Center.
We have also heard it’s often difficult to direct a patron to the appropriate webpage when at the circulation or information desk. In addition to the continually updated Device Resource Center online, we have put together an eBook Devices Cheat Sheet (PDF) that you can print out and make available to staff inside your library. This handy reference tool will empower any library staff member to provide patrons with information on compatible eBook readers.
The Cheat Sheet outlines the Barnes & Noble nook, the Sony Reader, and the Kobo eReader. Keep in mind, it isn’t necessary to own or use an eBook reading device to enjoy eBooks. As we’ve listed on the Cheat Sheet, you can use your Windows PC or Mac computer or laptop with Adobe Digital Editions installed.
With the holiday shopping season quickly approaching, you will undoubtedly receive an increased number of questions about eBooks and eBook reading devices. Feel free to use the eBook Devices Cheat Sheet as a reference tool to assist in answering eBook device related questions. As new devices are tested, we’ll update the sheet and let you know when an updated version is available.”