Can someone explain to me how the Amazon Prime Kindle lending library works?

I use it all the time. Here is how it works.

@Pachyderm_In_The_Room Thanks for that. I did see that, but I guess I didn’t phrase my question correctly. Are any books available for the lending library or only select ones?

Oh, sorry, I see now that you did ask that. I’ve come across the word “eligible” in several places on their site in conjunction with the lending library, so apparently not all Kindle books are borrow-able.

Not all are available and you can only borrow one at a time and, at least in my case, I can only do it once per month.

@Sueanne_Tremendous @Pachyderm_In_The_Room Do they ever do new releases or is it all books that have been out for awhile?

They keep on updating hourly the best selling new and future releases

Yes, only certain books are eligible for prime. The item will have a message indicating that it’s eligible for Prime on its product page.