Do you ever stop and think how amazing it is that your mobile phone can tell you exactly where you are in the world? You will after you’ve read these 18 interesting facts about GPS.

1. GPS is an acronym and stands for Global Positioning System.

2. However, some people say the G stands for ‘global’ others say it stands for ‘geo’.

3. It has its origins in the LORAN system used in WWII.

4. This was originally used for ships and planes to communicate over huge distances.

5. It’s based on the Doppler Effect.

6. This is where the frequency of a signal changes depending on how an object is moving relative to you.

7. GPS was first used by the U.S. military to coordinate training exercises.

8. In total, just 5 countries operate their own navigation system – USA, Russia, China, Japan, and India.

9. The Russian version is called GLONASS – Global’naya Navigatsionnaya Sputnikovaya Sistema.

10. Originally GPS was rather excitingly called ‘Navistar’.

11. The technology relies on satellites to make it possible, with the first one successfully launched all the way back in 1989.

12. President Reagan gave the world free access to GPS after a Korean airliner was shot down by mistake by the USSR in 1983.

13. The first cars with built-in GPS hit the road all the way back in 1996.

14. The current GPS system relies on 31 different satellites.

15. Shoes are now being developed with GPS installed, to help people with Alzheimer’s stay safe.

16. Current systems can pinpoint your location to within 10 metres.

17. GPS becomes more accurate in wide open spaces.

18. Solar storms are a regular threat to the satellites which make the system possible.