Black glasses with masking tape holding them together and a pocket protector are no longer a required part of the uniform for GPS owners. GPS has gone mainstream. But if you're still not up to date on what it is and how it works, and if you'd like some advice on what to buy, this article will bring you up to speed.

A GPS device is like a map on steroids. First of all, it always gives you that little "You Are Here" dot - you no longer need to figure that out for yourself. And all you need to do is tell it where you want to go and it will plot the course for you. It doesn't end there, however. New GPS units will provide you with voice guided directions for the entire trip, tell you where the nearest gas station is, and will even put you back on course if you take a wrong turn.

GPS stands for Global Positioning System, a system of 28 satellites orbiting earth. It was originally developed for military use, but its uses have spread far beyond just military applications. Your GPS unit can receive signals from these satellites, and by using these signals, calculates your position (within 3-10 meters), direction, altitude, and velocity. Once your GPS unit knows where you are, it can help you get to where you're going as long as it has mapping software installed. All but the most basic GPS devices currently have mapping software.

Now that you know a little bit about what a GPS device is and how it works, it's time to educate yourself on the features available and decide which unit will best suit your needs. There is certainly no shortage of GPS devices available, so doing a little research can save you a lot of time and hassle.

Step 1 - Which type of GPS do you need?

There are four main types of GPS units; the car navigation system, the portable outdoors unit, the marine system, and the PDA/GPS hybrid.

If you're mainly planning on using your GPS to get you from point A to B in your car and don't think you'd use it for much else, your best bet is the in-car navigation system. These systems can be built in to your car or you can purchase a device that mounts onto your dashboard. Desirable features for the in-car systems are: voice guided directions; detailed built in maps; touch screens; rerouting in case you get off course; and a database with points of interest to help you find the nearest gas station, restaurant, and many more places along your route.

If you're going to want a GPS device that isn't limited to the car, then you may want to consider a handheld GPS (http://www.gpsmaestro.com/handheld). These devices are ideal for anyone who loves to hike or bike. Features to look for in a handheld unit are: lightweight, rugged, waterproofing, long battery life, color screens, and mapping features. The handheld GPS units are geared towards people who spend a significant amount of time outside. For example, if you're out hiking you can easily track where you've been; mark your own points of interest; and even find out how far you've gone and at what speed. Many new handheld devices offer some navigation features while driving. You can even purchase handheld units that offer built in radios that will not only allow you to communicate with other members of your party, but will also display everyone's location on your screen.

If being on the water and fishing is your thing then you should probably consider a marine GPS. These units are specifically designed to be on and around water. All of these units will feature waterproofing and should have screens that are easy to read even in bright sunlight. Some other good features to look for are: color chart plotters, onshore and offshore maps, fish hotspots, and sonar capability. You may also want to consider a unit that will function as your car navigator, eliminating the need for two devices.

The final category of GPS device is the PDA/GPS hybrid. This device offers a good combination of the car navigation systems and handheld devices. You'll get the large screen that you'd find in the car system and the portability of a handheld unit. Also, you get a PDA to help you keep organized. One drawback is the limited selection of these units. Only a few companies have attempted to make an integrated unit, and all have some serious limitations.

If you are considering a PDA/GPS hybrid, I'd recommend you purchase the PDA separately from the GPS. Find a PDA that offers all the features you want in your PDA, then look for a GPS receiver that will attach to your PDA via Bluetooth. The features to watch for are the same as listed for the in car systems. All of the current PDA/GPS devices are better suited towards driving than hiking, although they do offer the portability for outdoor activities if needed. This category probably offers the most potential of the four, but it is also the newest, so watch for significant improvements in this category in the future.

Step 2 - Budget Considerations

If you're on a budget, then it's important to decide which features are most important to you. If you want a full featured car navigation system, it can easily run over $1000 (and over $2000 if you want one that's built in). If, however, it would be more of a toy to play with, then a handheld device could be a better choice as they can be as low as $100 and are rarely more than $500. Marine GPS devices vary widely in prices, but a very good device can usually be purchased for no more than $1000. If the PDA/GPS devices interest you, they typically range from $400-$900.

Step 3 - Where to Buy

Finding the right store to purchase your GPS device can be difficult. Most stores only carry one or two kinds of GPS. For example, if you go to a sporting goods store you're likely to find the handheld GPS units and marine GPS units but not the car navigation or the PDA/GPS hybrids. I actually prefer shopping online for GPS units as the prices will likely be lower, and you'll be able to read user reviews of the items before you buy. Just make sure that if you have a problem with your GPS you are able to return it.

Owning a GPS can be extremely helpful, especially if you tend to get lost a lot or if your glove compartment is overflowing with outdated maps. They can also make planning a long trip to an unfamiliar area a breeze. Deciding which GPS to purchase can be difficult, but as long as you make a list of the features you absolutely must have then all you have to do is find the units that match your budget. Read reviews from other owners and you should have no trouble at all. Once you purchase your own GPS unit, you'll wonder how you ever lived without one.

About The Author Gary Ruplinger is the webmaster and writer for GPS Maestro, site offering tips, tools, and reviews for GPS Devices. To learn more, please visit http://www.gpsmaestro.com.

This article was posted on December 10, 2005