Introduction

Since the dawn of time people needed a guide to get them where they wanted to go and back again. Today, the Global Positioning System has revolutionized how people travel and function every day. In the modern world, GPS generally assists people with travel but is useful in other areas of life. The GPS system we know today did not appear out of thin air. It has evolved over time from various developments in navigation. An early method to determine position was a compass. By using a magnetized pointer and Earth's magnetic field, a compass could point anyone in the direction they wanted to go. Recently the compass has been supplanted by a more advanced GPS device. The original GPS was known as the Navstar Global Positioning System and was first brainstormed at the Pentagon in 1973. In 1978 the first operational GPS satellite was launched. By the mid 1990s the system was fully operational with 24 satellites (James, 2009). Randy James (2009) describes how the current positioning system functions and how it uses satellites, By calculating the difference between radio signals received from four or more satellites, GPS receivers on the ground can determine their own location, speed and elevation with great accuracy - usually within a few meters or even less. Satellites are regularly replaced as they age and fail; there are currently more than 30 in space, with the extras used as spares and backup. Since the mid 1990s this satellite positioning system has made its imprint in the everyday lives of people.