The Global Positioning System, or GPS, kicked off in 1973 by the US Department of Defense.
GPS didn't just appear overnight, though. In 1972, Bradford Parkinson, a US Air Force Colonel, was tasked with developing the first satellite navigation program. He led a team to revise a system that synthesized all of the best aspects of other existing systems, which led to the approval for the first 24-satellite GPS system that launched in 1978.
Interestingly enough, GPS wasn't fully operational until 1993 (although it was used by the US military during the Gulf War), didn't hit the first cellular device until 1999, and only shortly after made its way to the first motor vehicles.
Today, we use GPS for nearly every aspect of our daily lives, from Google Maps to maritime navigation. As more GNSS systems are developed by other countries, we should continue to see improvements in GPS accuracy and applications.