Amazon Kindle is a software and hardware platform developed by Amazon.com subsidiary Lab126 for rendering and displaying e-books and other digital media. Three hardware devices, known as "Kindle", "Kindle 2," and "Kindle DX" support this platform, as does an iPhone application called "Kindle for iPhone". The first device was released in the United States on November 19, 2007.
The Kindle hardware device uses an E Ink brand electronic paper display, and is able to download content over Amazon Whispernet using the Sprint EVDO in the USA or, for newer Kindle 2 devices, AT&T's network internationally. The Kindle hardware device can be used without a computer, and Whispernet is accessible without any fee. These devices also provide free access to the internet. Kindle devices sold prior to October 19, 2009 were sold only in the United States. On October 7, 2009, Amazon announced an international version of the Kindle 2 with a built-in 3G (HSDPA) and EDGE/GSM wireless modem for connectivity in over 100 countries, which went on sale October 19, 2009 worldwide.
On March 3, 2009, Amazon.com launched an application entitled Kindle for iPhone in the App Store for iPhone and iPod Touch owners to read Kindle content. Through a technology termed "Whispersync," customers can keep their place across Kindle hardware devices and other mobile devices.
Amazon announced the Kindle DX on May 6, 2009. This device has a larger screen than its predecessors and supports PDF files natively. It is marketed as more suitable for displaying newspaper and textbook content.
Amazon has released "Kindle for PC" as a free software download for reading Kindle books on a Windows PC.
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http://en.wikipedia.org/wiki/Amazon_Kindle