Imagine holding a library of books in the palm of your hand, searching them in seconds and reading them on crisp screens that look as good as paper. Now imagine going into a bookshop that’s not your regular one and being told that the novel you want to buy is written in a language you can’t understand, or that the novel a friend has lent you is indecipherable. Welcome to the world of ebooks.

Last week, Sony and Waterstone’s, the UK’s largest chain of bookshops, launched the Sony Reader, a paperback-sized device that can hold up to 160 ebooks in its memory. A crisp, monochrome 6in screen lets you skip through pages and magnify text. In Sunday Times tests, the screen was easy to read both in bright light and indoors, and the unit’s slim metal case felt tough and well made. Flicking through electronic pages using the control pad was easy, although the menus were rather slow to respond.

However, unlike Amazon’s Kindle ebook reader, launched last year in the US and expected to go on sale here soon, there’s no way to search inside text (for characters’ names, for instance), look up words in a dictionary or download ebooks to it without using a computer.

The Sony is selling for £199 and comes with a disc containing 100 classic (and conveniently out-of-copyright) books, which you can load onto your Reader using a home computer. When you’ve exhausted these, you can download more from the 4,638 titles on sale at www.waterstones.com at a 20% discount on the cover price.

A tempting offer . . . until you discover that ebooks bought for the Sony Reader can’t be copied, shared with your friends or transferred onto other makes of reader. Nor can you buy ebooks for the Sony from some rival bookstores, including Amazon and Borders. The cause is digital rights management (DRM), the copy protection technology similar to that used by Apple’s iTunes online store. Many book publishers are nervous about consumers freely copying and sharing ebooks and have insisted that every new ebook includes DRM.

The problem is that three major UK booksellers are each touting their own ebook readers with three different DRM systems – none of which is compatible with any of the others. Waterstone’s and Sony are using the popular EPUB format; Borders has partnered with iRex, a spin-off company from Philips, that prefers PRC (Mobipocket) files; and Amazon is likely to use its proprietary AZW format for the UK launch of the Kindle.

This aside, the three readers are quite similar. All use innovative “E Ink” screens that use far less power than traditional laptop or mobile phone displays, and can be viewed without strain for hours, from almost any angle. They currently only display in black and white, and all three black out the display for a moment when turning a page. All can, if required, read material transferred from your computer in other formats. Plain text files, Adobe PDF documents and basic Jpeg images are all compatible, so you can read, say, a car maintenance manual stored on your laptop as a PDF.

The iRex iLiad (£399) sports a large 8in touchscreen that lets you scribble digital notes in the margins of ebooks, and wi-fi connectivity. It’s heavier and somewhat clumsier to use than the Sony Reader, although it too comes with 50 classics.

In the US, Amazon’s Kindle, with a 6in screen and enough memory for 200 ebooks, has helped boost ebook sales to around $17m (£10m) in the first half of this year. The Kindle costs $359 (£202), but includes a free mobile internet connection for downloading books while away from a computer, for subscribing to daily newspapers or blogs, and even for basic web browsing. Two new Kindles are believed to be in the pipeline for next year: one matching the slimline style of Sony’s Reader, the other with a larger screen suitable for academic books.

So why the insistence on locking readers into a single retailer? Part of the reason could be that ebooks are still relatively new, with standards that have yet to be finalised. It’s also likely that each company hopes to dominate the ebook market the way Apple does online music sales. Apple’s iTunes store enforces its own DRM system and still accounts for about 80% of digital downloads.

There may yet be a way out of this DRM nightmare. WH Smith offers its ebooks in a variety of formats to suit most readers (except the Kindle), and there are dozens of websites that sell ebooks without DRM protection or even allow completely free downloads. Project Gutenberg (www.gutenberg.org ), for example, offers more than 25,000 free downloads that should work on all three readers here – although you won’t find the latest airport blockbusters among its classic and out-of-print titles.

As ebooks become more popular, they are also spreading beyond dedicated reader devices. There is a choice of ebook software for the iPhone, for example.

If there’s a message to take away from all this, it’s don’t plump for a reader before you’re ready: ebooks are not predicted to make up even 1% of book sales until 2010. This first generation of ebook readers may suit frequent travellers and bookworms, but make your choice too early and your ebook story may not have a happy ending.

- The Sony Reader has built-in memory to store around 160 ebooks, as well as two memory card slots to allow for thousands more

- The bookmark button lets you mark your place in the text. The Reader can store hundreds of bookmarks for each ebook The Reader’s metal case feels tougher, lighter and slimmer (at 8mm) than its rivals

- The 6in E Ink display works well in low light, although you will need the £39 PRS-ACL1 backlight case to use the Reader in the dark

- Thumb-operated buttons flick from one page to the next and back. The E Ink screen blacks out between every page turn

HOW THE RIVALS MATCH UP

Sony PRS505 Reader
Price£199
Screen size6in
Memory192MB, MS and SD cards
Holds160 books
ConnectivityUSB
Battery life15 hours
Weight9oz

iRex iLiad
Price£399
Screen size8in
Memory128MB, MMC and CF cards
Holds80 books
Connectivitywi-fi, USB
Battery life10 hours
Weight15.3oz

Amazon Kindle
Price$359 (£202, available in US only)
Screen size6in
Memory180MB, SD card
Holds200 books
ConnectivityMobile internet, USB
Battery life7 hours
Weight10.3oz

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