Here, from New York Times and National Geographic contributor (and IntelliTours founder) Jim Carrier, is the fascinating, little-known story of the discovery, development, and future of GPS, the greatest advance in navigation ever fielded and a mighty electronic glue binding the modern world together. Fifty years from now historians will place GPS on the short list of inventions, alongside the clock, electricity, and the Internet, that are truly indispensable, Carrier writes. We cannot imagine living without it. In fact, without GPS, civilization as we have come to expect it would sink into chaos.

On any given day, GPS saves lives and takes lives, tracks bears and convicts, guides us to Grandmas house, and helps deliver FedX packages along the most efficient route. But few realize how much GPS has seeped into the very infrastructure of our civilization, delivering time for ATM withdrawals, high-line power, and international stock exchanges, and navigation for oil platforms, corn farmers, pilots and the blind. Born in the Cold War to guide Polaris missiles, satellite navigation has now become imbedded in thousands of civilian applications with an estimated annual economic impact of $122 billion.

Read more and order Jim Carrier's latest book.

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