Amazon has officially announced its long-anticipated Kindle e-book reader and provided full details of the device, which is available now in the US on Amazon.com. News of the Kindle's imminent release first hit the web last week.

The Kindle - Amazon's first foray into making its own hardware - weighs 10.3 ounces, can contain up to 200 books, has a keyboard, and uses electronic ink display technology.

Kindle operates without ever connecting to a PC. Instead, the device can download books - 90,000 at launch - directly via the built-in EVDO radio connection to Amazon's new Whispernet service.

Books take less than a minute to download and their price varies. New releases and New York Times bestsellers cost $9.99 (£5). The service runs on the Sprint EVDO network in the US; it carries no service charges or contracts - that's all covered in the background by Amazon. The e-book reader is on sale now at amazon.com for $399 (£200).

In addition to books, Kindle can automatically download newspapers and blogs, in a return of "push" technology. The device also has a dictionary and Wikipedia access.

Amazon has yet to reveal details of the Kindle's UK availability.