The handheld device can also hold several shelves' worth of books: 200 of them onboard, hundreds more on a memory card and a limitless amount in virtual library stacks maintained by Amazon. Also, the Kindle allows you to search within the book for a phrase or name.
Some of those features have been available on previous e-book devices, notably the Sony Reader. The Kindle's real breakthrough springs from a feature that its predecessors never offered: wireless connectivity, via a system called Whispernet. As a result, says Bezos, "This isn't a device, it's a service."Read more here.