Maps are quite useful, and there are all sorts of Web sites that offer maps and driving directions to a variety of places. However, the best map is not particularly helpful if you take a wrong turn somewhere and suddenly do not know where you are. Or how to get back to where you should be. This is where the Global Positioning System (GPS) comes in.

GPS was developed originally for the military. It dates back to the 1980s. But it is widely used among civilians now, and more cars are coming equipped with GPS systems. This is because the system uses satellites and triangulation to help determine where you are. Two satellites read your signal from the ground, and then the data is crunched to determine your exact location. Many GPS systems are advanced enough that you can let it know a destination, and then it can provide you with directions on how to get there. Some cars come with GPS systems programmed to talk, so that you can have audible directions like ?turn left onto 3rd Street.?

But GPS isn't just for driving. Many hikers use their GPS in tandem with their maps to help them stay on track. This is especially helpful in wilderness areas and backcountry, where there aren't always clearly marked trails. But in such cases it is also important to have an actual map. Because even though GPS can be helpful, the fancier systems that do more than give you a location can be very expensive. And good map knowledge is always helpful due to the fact that GPS has its limitations.

First of all, if you can't get the signals from two satellites, the GPS is useless. This is because two satellites are needed to triangulate your position. In some areas, the satellite signal might be blocked by trees, mountains, or other obstacles. Another thing you have to worry about is battery power. A GPS will not just run indefinitely. Eventually it will run out of juice. Most GPS are rechargeable, but if you are out in the middle of nowhere, without a charger, the GPS is useless. When spending extended time in the wilderness or backpacking, it is a good idea only to your GPS occasionally, to check your position and plot it out on the map.

A fun twist on using GPS for recreation is what is known as geocaching. Someone hides something unique and distinct somewhere, often a clue to the next location. You use a map and a GPS to find the location and get the next clue. Valuables are usually not part of this sort of activity. However, many people find it intriguing, challenging, and fun to head out armed with a map and a GPS to ?discover? something. These geocaching groups are rising in popularity, and can be found just about anywhere in the world.

While GPS is certainly useful, it does not appear that it will completely replace maps anytime really soon. But it makes an excellent complement and help to any map.