"Discovering the Secret World: Coral Reef" by Radka Piro is a children's board book from the Peek inside series. It is illustrated by Sojdr, Martin and measures 9 inches in length, 9 inches in width, and 0.6 inches in height. The book, published by Fox Chapel Publishing Company, explores the topics of science, nature, and marine life with 14 pages filled with information about coral reefs and fish species.