Mr. Gardner writes in an entertaining and easy-to-understand style, and his explanations are precise and informative.
Having been written in 1988, the book still dedicates a good portion of its content to the Soviet communist economic system, which is now a "distant" memory. Still, it's a good reminder of how divided the world was economically and philosophically for almost the entire 20th Century.
All in all, a must read for people who want to learn the basics (and a lot of nuances) of the main economic systems of the world