Since the GPS started in 1993 it has become quickly an essential global utility, indispensable for all types of modern navigation. The Global Positioning System (GPS) is a worldwide navigation system formed from multiple satellites orbiting the earth. Each satellite broadcasts precise timing signals. GPS receivers collect those signals and calculate their current position (latitude, longitude, elevation) in real time.

For further technical information on the Global Positioning System please follow the link http://en.wikipedia.org/wiki/GPS

GSM TECHNOLOGY

The Global System for Mobile communications (GSM) is the most popular standard for mobile phones. The system allows sending and receiving digital data such as voice messages and text messages.