Buying a Global Positioning System (GPS) to meet your needs may not be as simple as one might think. There are a myriad of different devices, for many different purposes.The first thing to consider when buying a GPS device is its primary use. Will you be using it on the road, on the trail, or on the water?On the road devices are usually temporary mounted in the vehicle with suction cups or bean bags. Most of these devices have turn-by-turn instructions and auto correction if you miss a turn. I would highly recommend getting a device with the auto-correction feature, that way you don’t have to mess with the device if you take a wrong turn, it will recalculate the route for you automatically. There are some devices that are also portable, so you can unplug them from your vehicle and take them with you as you walk around in a large city. My favorite in this category is the Garmin c330, c340, and c530 series. They are a wonderful size for using it in the vehicle and small enough to use as a portable. They have city maps pre-loaded, so they are not much use off-road. Many of the newest designs have built in picture viewers, MP3 players, traffic updates (careful, that usually costs extra!!), and many other bells and whistles. One of the best features of the Garmin c-series line is the ability to ask for the closest landmarks, such as food, gas, shopping, golf courses, etc. Make sure you understand what it has and what you want to use for before making the final decision.One of the most asked questions is should I buy the car with GPS already in it? Personally, I don’t like that option because it limits how you can upgrade, and the device cannot be used in multiple vehicles. Some car manufacturers are charging several hundred dollars to update the map data on these devices and you have little choice in using them to do this. The GPS market is an ever changing market and I like to be in control of which device I want to purchase. Having said that, I am choosing to have a device mounted to my dash or windshield (suction cups….also illegal in some states, so make sure you know which ones!!!) with wires trailing to the power source. Some folks don’t like that, it is a trade off you have to decide on.On the trail devices are handhelds which depict topographical, or basic mapping data, not detailed street level details. These are great for hiking and geocaching. They have the ability to either import coordinate, or download coordinates of a location and then tell you how close you are to that point and which way you need to go to get there. For hiking, you can set different points as you walk, like a breadcrumb trail so you can get yourself out the way you came in. These devices range from $80-$500+ depending on the different capabilities of the device. Some of the higher end models allow you to buy pre-loaded map detail on memory cards, so they can double as driving directions, however, they still don’t have the turn-by-turn capabilities.GPS devices used on the water are fixed mount devices. These devices can have water depth, temperature, etc, especially helpful for the fisherman. Maps that can be downloaded can have tidal waters, known shipwrecks, ports, and are very detailed. There is a huge range of devices to consider in this area.Keep in mind that mapping software used on these devices changes about 1-2 times per year. Less frequently for the maps on the water. Understand what your devices downloading capabilities are so you don’t get stuck with outdated maps forever! Also beware that because maps change, you have to be somewhat flexible when following the directions. I have had instances where it tells you to “turn left here”, only to have that be the wrong way on a one-way street!!! In other words, these are guides to get you close to where you need to be, you cannot use them as gospel….common sense should prevail!