Ninjas are known for their unorthodox warfare! Discover the origin of ninjas, their historical development, famous ninjas, key skills and traits, and details about weapons, training, and missions. Fast facts, maps, infographics, a glossary, timeline, index, and historical and color photos supplement easy-to-read text. Aligned to Common Core Standards and correlated to state standards. Checkerboard Library is an imprint of Abdo Publishing, a division of ABDO.