E-books are gaining in popularity, but there are still some issues that hold them back from widespread pick-up. File format wars are one of them.

If you want to read an e-book, you first have to decide which reading device you’ll commit to: your PC, a Kindle, your iPhone, a Sony Reader? Books available for one device are not always available on another, and if you want to switch devices at a later date you may lose all your books.

As a publisher, you must decide which e-book formats you should invest money in producing: one, some, all? Which has the bigger audience? Who will be around for the long-term?

In the 1990s, the dizzying array of e-book formats confused the market and hobbled the industry’s success. Today, to avoid a repeat of history, a consortium of publishers, booksellers, authors, and software publishers are calling for the book industry to rally around a single file format. That rally point is ePub, a free and open digital book format based on XHTML. “Open” means the files are not protected with DRM (Digital Rights Management) technology, and can be freely read by any hardware or software with ePub capability.

A single unlocked file format makes life easier for everyone. With an ePub standard in place, you (as the publisher) only need to create a single digital version of your e-books, saving you time, money, and headaches. Readers can be assured of having access to all the e-books they want on whatever device they choose, and can even switch between different devices without losing access to their library.

The ePub format, launched in late 2007, is still relatively new but gaining good momentum. Though there’s still a long way to go yet, some believe that 2009 will be the year ePub truly becomes the industry standard.

The ePub Blog is a good resource for more information. It includes a list of devices that can read ePub files, as well as places you can download ePub books.