To say there were many inventions in the 20th century would be a massive understatement. This series, as the title suggests, highlights some of the century's most-prolific innovations. Each hourlong episode focuses on a decade in the 20th century. The airplane, the DNA fingerprint, the radio and the machine gun are some of the inventions that are featured in this series. But it's not just successful inventions that are featured. ``Inventions That Shook the World'' also looks at some not-so-great inventions that failed.