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You and your approved contacts can send documents to your registered Kindle devices, free Kindle reading applications, and your Kindle Library in the Amazon Cloud by e-mailing them to your Send-to-Kindle e-mail address ([name]@kindle.com). Your Send-to-Kindle e-mail address is a unique e-mail address assigned to each of your Kindle devices and free Kindle reading applications upon registration.
PDFs can be converted to the Kindle format so you can take advantage of functionality such as variable font size, annotations, and Whispersync. To have a document converted to Kindle format (.azw), the subject line should be "convert" when e-mailing a personal document to your Send-to-Kindle address.
Your newly purchased title/eBook from Write Out should now appear in your Kindle library.
To find more information about how to use your Send-to-Kindle e-mail address, please visit Amazon's Help Page.