What: Lend your Kindle eBooks purchased from Amazon. Keep in mind though, once you lend the book, it will be gone from your own library until it's returned, so make sure you're not in the middle of reading it!
Where: All you need is the Kindle app or a Kindle device
When: Anytime! Just make sure to accept the loaned book within 7 days, otherwise it will return to your friend's library. You can keep the loaned book on your device or app for 14 days.
Why: Share the love, share the books!
This is what it will look like if you can lend the book to someone. Notice the bottom option, "Loan this title."
If you cannot lend out the Kindle book, that option will not be there.
For more information visit Amazon