Discover Series Books for Babies & Toddlers Is your child fascinated with the armed forces? Want to share a family history of patriotism and service? Military (Book 2) is the second in a series of picture books featuring photographs of objects from the Army, Navy, Air Force and Marines. Used as a jumpstart for interaction, Discover Series Picture Books are a great way to introduce new images, words and concepts to kids. Use this photo dictionary as a learning tool. Each photo has a clear title beneath it for identification. Language learners, children, and people looking to build their vocabulary can use this simple book to learn new words.