This title examines the development of the artillery, tanks, U-boats, chemical warfare, and aircraft used during World War I. Compelling narrative text and well-chosen historical photographs and primary sources make this book perfect for report writing. Features include a glossary, a selected bibliography, websites, source notes, and an index, plus a timeline and essential facts. Aligned to Common Core Standards and correlated to state standards. Essential Library is an imprint of Abdo Publishing, a division of ABDO.