
Kindle Unlimited (KU) is a subscription service available to some customers in select countries where subscribers can read as many ebooks books as they like and keep them as long as they like as long as they pay the monthly fee. KU can be used in the U.S., U.K., France (Abonnement Kindle), Mexico, Brazil, Spain, Canada, India, Germany, Australia, Italy, and Japan.

When someone signs up for KU and goes to the detail page for your book, the Kindle Unlimited price of $0.00 will appear.
When you enroll in KDP Select, your book is automatically available to Kindle Unlimited subscribers. It remains enrolled unless you choose not to have your book registered in KDP Select.

You don’t earn royalties on books read via KU, however you will receive a share of the KDP Select Global Fund based on the number of pages a KU member reads in your book the first time. You can find information on how many pages KU or KOLL members have read each month on your KDP reports page under the subheading Kindle Edition Normalized Pages (KENP).
Assignment: Sign up for KDP Select to take advantage of Kindle Unlimited.