If you've been confounded by all the technical jargon and

hype surrounding GPS, confusing what's turning out to be a

very useful tool, allow me to shed a little light on your

roadmap to deciding whether or not this technology is for

you! Originally designed with military applications in mind,

the technology was made available to mere mortals in hte

1980's for the many and varied uses we've found so far for

these special tools. Not only handy for auto navigation, GPS

units have made their way into maritime navigation,

backcountry uses, and much, much more!How does GPS work? GPS (which stands for Global Positioning

System) allows you to pinpoint your position anywhere on the

planet to within an average of 15 meters, with some units

doing much better than that. Twenty-four GPS satellites,

paid for and placed in orbit by the Dept. of Defense

courtesy of your tax dollars, send signals back to terra

firma 24/7. These signals are retrieved by your handy dandy

GPS receiver which uses three sources (satellites) to

triangulate this information and compute your actual

position. If there are four data sources, even altitude can

be determined. Since there are normally eight satellites in

line of sight from anywhere on earth, the opportunity for

accurate positioning exists. Other things that can be

determined besides latitude, longitude, and altitude would

include things like speed, sunrises and sunsets, bearing,

distance and more. While they will work in any weather, some

hindrances would be electronic interference, buildings, and

certain terrain. A good rule of thumb is that the units will

generally not perform underwater, indoors, or underground.

There are currently two Global Navigation Satellite Systems

in use. Besides GPS, there is the Russian Global Navigation

Satellite System (GLONASS) Protocols are constantly being

refined to enhance the abilities of these systems. A bright

light on the horizon is Galileo, scheduled to go online in

2008, which promises even greater accuracy and

functionality. So how do I know which GPS unit is for me? Quite a few

choices now exist for consumers in the GPS marketplace.

Whether you need a handheld unit for backpacking or boating,

or one for your automobile (they are becoming an attractive

option!) or for one of a myriad of uses, there are several

reputable manufacturers of quality GPS units out there to

help you find your way through the maze of choices. Names

like Magellan, Garmin, Rino, Etrex and Meridian lead the

market, and are readily available. Take your time, check out

the various features each has to offer, and get yourself

outfitted with one of the more useful and efficient

navigational tools out there today!Keith Thompson is the webmaster at Best GPS Review where many resources

and information on GPS can be found.

Author:
Keith Thompson