A new Kindle must be registered to an Amazon account in order to purchase and download content. Registering a Kindle also allows for the transfer of purchases between devices.
Registering a Kindle to an already-existing Amazon account or to a newly set-up account allows the 1-Click payment feature to be set up. This feature allows users to search and shop for materials and then purchase them with one click.
If someone has given away a Kindle or no longer has it available, the Kindle can be de-registered from the Amazon account. The process is handled through the same screen as registration.