GPS systems have become one of the most sought after accessories that you are going to want to put into a car. A good GPS system will help you get to where you want to go without having to deal with bulky maps, as well as hard to read printed out instructions from your computer. You will also be able to avoid traffic jams which will allow you to get to where you want to go as quickly as you would like. To many car drivers, getting a good GPS system is just as important as having a great sound system in their car. Many consumers want to know just how these systems work and if they really worth the price to purchase and install in their car. The most basic function of a global positioning system is to pinpoint an exact location and then help someone get to the position that has been marked on the GPS. Now what a consumer actually purchases is a Global Positioning System receiver, not an actual system. The actual GPS system is a collection of well over two dozen well placed satellites that have been military installed in the orbit of the earth. All of these satellites complete an orbit around the earth two times each day. Anyone who owns a GPS receiver will be able to get access to at least four of these satellites. So at any given time you will be able arrive at your exact location. GPS systems can operate accurately in a number of conditions, but they are not infallible. For example, GPS is accurate regardless of weather conditions or the time of day. The signals, however, can be blocked by thick forests, canyon walls, large buildings and other similar obstacles. On average, GPS systems are accurate within 15 meters, but some newer machines have a margin of error that is even less. The signals that you are able to pick up with your GPS are essentially free; however, it is through the services that motorists are required to pay for that allows you to navigate from place to place. And due to the fantastic backing systems that GPS has, you will be able to benefit from some very helpful extras -- which will help make your travel go even more smoothly. Travel will soon become easier than it has ever been when you get a GPS to help you navigate. A there are a few really great extras that you will get through a paid service. With the features that you receive through paid GPS service, you will be able to make use of things like road map functions. This will help you download the information that you need to pretty much walk your way step-by-step right to your destination. There are also systems that give you verbal turn-by-turn directions to where your destination happens to be. Real-time traffic updates " Some services enable motorists to receive real-time traffic updates as they travel along a route. Intuitive services will help motorists avoid jams ahead and provide them alternative routes to take to avoid problems. Trip planning " When the GPS system is backed by a computerized service, motorists can receive invaluable information for trip planning. Not only will a GPS system in a car determine the best route for a motorist to take, but it can also calculate travel time, distance and other important factors. So now you know that a good GPS system is going to be able to assist you in knowing exactly where you are -- at all times -- while you are driving. A true GPS receiver enables people to determine exactly where in the world they are at any given time.