bop is a photo book service that takes up to 30 images uploaded by a user each month from their digital cameras and devices and formats them into a printed photo book. bop adds relevant advertisements to the backs of the photos based on the user's profile information. The service is free for users, with all costs covered by advertising revenue. bop prints the user's photo books and ships them each month, allowing users to archive their photo memories and share printed copies with friends and family for free. The targeted advertisements are paired with users' cherished photo memories in a way that traditional online or disposable ads are not.