Format wars are a mixed blessing for consumers. Whether it's Betamax versus VHS or Blu-Ray versus HD-DVD, the consumer ultimately wins because companies have to advance superior technologies. But problems arise if the format you backed loses the war - and your device becomes next year's expensive doorstop.
A new fight is emerging in epublishing between Apple iBooks and Amazon Kindle, with skirmishes between Barnes & Noble, Kobo and others. But the real battle is between the underlying formats: EPUB 3 and KF8.
So far, this particular format war has been waged rather quietly, but it's a war that will affect you more than you might realise: two rich, powerful and mighty West Coast tech companies could soon end up as gate-keepers to the world's literary works. And if we've learned anything about West Coast tech companies, it's that once they've got the data, they want you're pretty much at their mercy.
EPUB has quietly emerged as the unassuming but widely accepted open format among publishers. Apple wisely chose EPUB for iBooks, and the format is used in countless other ereaders and devices – including, significantly, both Kobo and Barnes & Noble's Nook. EPUB's guardian, the International Digital Publishing Forum (IDPF), ratified its long-awaited update, EPUB 3, in October 2011, updating the spec in a number of key ways that make it truly "next-gen".
It defines extensions (and a few restrictions) to its HTML5 base – including MathML support – as well as UI triggers, so audio and video elements can be activated without scripting. Scripting was also possible in EPUB 2 but actively discouraged; the spec has now progressed to the far more permissive "optional". This is a significant step, as ebooks can now be interactive – provided the scripting can degrade gracefully for ereaders that interpreted "optional" as "no".
Amazon, meanwhile, has gone solo with KF8 (Kindle Format 8). It replaces .azw, essentially the .mobi format with added DRM. Bezos & Co adopted .mobi when they bought MobiPocket in 2005, and it has been used in all Kindle ereaders since. KF8 is far more versatile. Initially it is only on the Kindle Fire, but will be back ported to the newer e-ink Kindles and to the Windows version of their ereader.
KF8 is based on HTML5 and CSS – just like EPUB 3 – but is more restricted. Only a subset of tags and styles are supported. In particular, the <script> tag is reserved for Amazon use only. <canvas> is also not supported, though this isn't surprising as it wouldn't be much use without scripting capability.
These differences start to matter when you begin shelling out money to grow your ebook collection. So which ebook format should you back? It may seem like the decision is already sealed when you buy the hardware: iPad equals iBooks/EPUB 3 and Kindle is KF8.
But the waters are muddier. The Kindle app is of course also available on iOS devices, so you could equally buy KF8-based ebooks for your iPad. And as of last month, Amazon relaxed its stranglehold, allowing third-party Android e-reader apps to be installed – so EPUB 3 (the more open format, assuming no DRM shenanigans) can be viewed on your Kindle Fire.
The main restrictions are that if you buy an EPUB title through iBookstore, it stays on your Apple-authorised device, and if you buy a KF8 title, it goes no further than your Kindle. You could strip the DRM and then do as you please, but even for personal use that's a legal grey area.
Apple, oddly given their runaway success in other areas of digital consumerism, remains the ebooks underdog, with sales of iBooks titles dwarfed by Kindle. But that's set to change.