What It Is and How It Works ? For the uninitiated, GPS stands for Global Positioning System. It's a method of finding a receiver anywhere on earth or in orbit, and it's arguably one of the most important inventions of our time. GPS has so many different applications that many technologies and ways of working are continually being improved in order to make the most of it. Now why is GPS so important and useful? First, we have to understand how it works.

In order to work, a satellite network orbiting the earth is used. The signals that are broadcast by the satellites carry data that is passed from the aerial, decoded and used by to the GPS software. The information is specific enough that the GPS software can identify the satellite, it's location in space, and calculate the time that the signal took to travel from the satellite to the GPS receiver. Using different signals from different satellites, the GPS software is able to calculate the position of the receiver.

Mapping It Out ? Even getting the information about the receiver's location will be useless without something to compare it with. The mapping part of any GPS software is very important; it is how GPS works our possible routes, and allows the user to plan trips in advance. Actually, the mapping data is what makes a GPS device expensive. This should be updated regularly and frequently in order to be accurate.

Several kinds of maps are created for different users. Road users, for example, require that their mapping data contains accurate information about the road network in the region that they will be traveling in, but will not require detailed information about the lie of the land. Hikers, however, might require a more detailed map about the local terrain, water spots, and tracks or trails, but they won't need extensive information about the road systems. Marine users need very specific information relating to the sea bed, navigable channels, and other pieces of maritime data that enables them to navigate safely.

And what about fishermen? They also use marine GPS to keep track of the movements of fish in real time and to predict where they'll be the next day. The advent of GPS fixing has also meant that co-operative fishing has become much easier, where several boats relay their locations to each other while they locate the best fishing waters. Special kinds of marine GPS, known as fishfinders, also combine several functions in one to help fishermen.

Get Started with GPS ? Consumers can avail of several GPS devices that are specifically designed for a variety of uses and functions. In-car systems have advanced features like voice guidance, dynamic route calculations, and even upgrading your maps from a CD-ROM. Then there are handheld GPS devices, such as those from Magellan and Garmin, which store a map inside, and are usually designed for outdoor use. They do not have detailed road information and the user has to find his own way from point A to point B without any route calculations.

Recently, PDAs and even a few sophisticated mobile phones have incorporated GPS technology into their own systems. A GPS receiver can be easily attached to these devices, so these tend to be the cheapest, easiest to use and most flexible solutions. Bluetooth technology has also started to make use of GPS, using a single PDA device wirelessly connected to several receivers.