A U.S. passport book is a government-issued photo identification document that can be used to travel internationally. Passport books contain blank pages for officials to stamp when leaving or arriving in a new country. They also have a 9-digit passport book number on the upper-right corner of the second page, or on the same page as the passport photo.
U.S. passport books can be used to fly internationally, unlike passport cards, which can only be used to travel by land or sea to specific countries. Passport books are valid for 10 years for adults, and 5 years for children under 16.
Passports prices are as follows:
Books for adults: $135 new, $110 for renewals
Books for minors: $105
Cards for adults: $55 new, $30 for renewals
Card for minors: $40