GPS was developed by the United States Department of Defense. It was named NAVSTAR GPS by Mr.John Walsh. The first satellite navigation system,“transit”, used by the United States Navy was successfully tested in It used 5 satellites that provided a navigational fix once per hour.

The cost to maintaining the orbiting GPS satellites is 750 million dollars. However, these costs are paid for by the united states government as a public good.The First GPS was available in 1993 for around 450 dollars. In present day you can get a personal GPS for walking in the woods, your car, boat or plane.

Some Changes… Since the release of the first GPS there have been 24 satellites launched for more accurate positioning. As roads are built and changed, the GPS owner must purchase an update disk. Larger LCD touch screens More user friendly soft wear.

GPS units are used in the United States Military for precision guided weapons Aircraft and Cruise ships. Submarines, Tanks and other military vehicles Coast Guard and Search and Rescue Personal Units.

$$$Price Ranges$$$ Hand held GPS units $80.00-$ Car/Truck GPS units $ $ Marine GPS units $ $ Aviation GPS units $ $

In the I expect that GPS units will be able to pinpoint your exact location, and even drive your car for you like an auto pilot.

There are 4 satellites at all times sending a signal to a personal GPS GPS units use an atomic clock witch is accurate to 1 billionth of a second Inspiration for personal GPS units came from the Russians launch of Sputnik The oldest satellite launched for GPS August “91” is still in use The most recent GPS satellite launched was in November 17, 2006.

Sources Google Images. En.wikipedia.org/wiki/Global_Positioning_System Beyonddiscovery.org/content/view.article.asp?a=458 Futureshop.ca Gpscentral.ca/products