- Amazon's rules allow you to download Kindle books on up to six other devices at one time -- including other Kindles -- as long as they're registered to your Amazon account. Amazon offers free Kindle software for non-Kindle devices, including computers, Apple's iPhone and iPod Touch and some BlackBerry models.
- Some Kindle books also have lending enabled, which means you can send that Kindle book to anyone -- whether that person has a Kindle or not -- for a single loan period of up to 14 days. When you look at the book's information in your Amazon account, you can see whether or not lending is enabled for any particular book. If you want to loan it to someone, you can then click the button and follow the prompts to send that book to your friend or family member. Once the friend or family member accepts the loan, you will not be able to access that book in your Kindle library until it is returned to you. A person to whom the book is loaned can return the book to your collection prior to the expiration of the 14-day loan period.
- Digital rights management is an option that publishers can choose to turn on and off when they make books available for the Kindle. Ways to fine-tune this option include determining how many devices a book can reside on at one time, as well as whether or not lending is enabled for a specific book. The publisher chooses whether one device or all six can view a book at the same time. As of April 2011, this information is not displayed when you purchase Kindle books.
- Amazon and other websites have free books available for the Kindle as well. Some are classic works no longer within the bounds of copyright, and have been converted to Kindle format by volunteers. Others are teasers from small publishers hoping to raise interest in their authors' works. These books can be downloaded to as many devices as you want -- Kindles or otherwise.