What do nails, hammers, axes, and human teeth have in common? They're all examples of wedges. This fascinating simple machine takes many important forms that shape how humans interact with the world. This innovative book introduces readers to real-world examples of the wedge and thoroughly explains how this tool works. Detailed pictures with extensive annotations explain essential engineering concepts. "Technology in Action" spreads give readers an inside look at wedges in action. This accessible book introduces readers to simple machines in a fun way, encouraging an early interest in STEM. --www.rosenpublishing.com.