Wheels and axles may seem basic, but with these inventions humankind has created incredible things. From skateboards to Ferris wheels, these simple machines have changed our world forever. This accessible book helps readers relate wheels and axles to the technology in their daily lives through cool real-world examples. Detailed pictures of machinery with extensive annotations help readers understand key engineering concepts. Fun "Technology in Action" spreads give readers an up-close look at how mechanical parts work together. This vibrant and engaging approach to simple machines is sure to encourage a passion for STEM, making this volume a valuable addition to any library or classroom.