by conner hall


The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS was originally intended for military applications, but in the 1980s, the government made the system available for civilian use. GPS works in any weather conditions, anywhere in the world, 24 hours a day. There are no subscription fees or setup charges to use GPS.

How it works

GPS satellites circle the earth twice a day in a very precise orbit and transmit signal information to earth. GPS receivers take this information and use triangulation to calculate the user's exact location. Essentially, the GPS receiver compares the time a signal was transmitted by a satellite with the time it was received. The time difference tells the GPS receiver how far away the satellite is. Now, with distance measurements from a few more satellites, the receiver can determine the user's position and display it on the unit's electronic map

How accurate is it

Today's GPS receivers are extremely accurate, thanks to their  design. Garmin's  parallel channel receivers are quick to lock onto satellites when first turned on and they maintain strong locks, even in dense foliage or urban settings with tall buildings. Certain  sources of error can affect the accuracy of GPS receivers. GPS receivers are accurate to within 15 meters on average.

Who invented GPS

Roger Easton was a contributing individual among a group of individuals including Ivan Getting, Colonel Brad Parkinson, James Buisson, Thomas McCaskill, Don Lynch, Charles A. Bartholomew and Randolph Zirn. As is the case with many "inventions", there were numerous parallel efforts, and many committees involved. Approximately $12 bilion was spent to develop the program..

GPS apps

this is a perfect app for people who need to track mileage for reimbursement.If you need to really keep track of where you are going and how much time and money you are spending, this is the perfect app for you!Automilez has a sweet interface, but you do need to create a free account first. Then you simply add in your odometer reading when you start and click “stop” when you are done!