The Kindle hardware device uses an E Ink
brand electronic paper
display that features 16 shades of gray. It wirelessly downloads content over Amazon's Whispernet using the Sprint EVDO
network in the USA. Newer Kindle 2 devices use AT&T
's network and its roaming partners for international wireless access.
The Kindle hardware device is used without a computer connection, and Amazon Whispernet is accessible without any monthly fee or wireless subscription.
All Kindle models provide free access to the Internet in the U.S. over cellular networks.