GPS devices have a lot of different components. The essential parts are the units people carry and the series of satellites, three of which are used to locate where you are while another is used alongside them in a process called triangulation to calculate your altitude.



GPS devices come in a variety of prices. As would be expected, the more expensive models offer more features than a basic unit. The very basic GPS devices will usually have a display and controls so you can determine your latitude and longitude. Some models offer a different number of waypoints which is for terrestrial coordinates such as longitude, latitude and altitude among others.

The term waypoint is also used to describe the number of landmarks displayed on a GPS device. This feature is found on different models, but not all units. What is displayed will vary depending on the map loaded, but the more displayed is not always ?merrier? as sometimes the screen can become too full and hard to read.

The higher priced GPS units will offer features such as a digital compass, or the ability to download area maps, zoom, relocate and even change maps. Some models offer features like back-lighting allowing you to read them at night without a flashlight. Some also offer a tracking system so you can go back and recall where you have already been.

Garmin is the leading manufacturer, but there are many others where you will find options for weight, control placement and battery life. Some GPS models are waterproof which is a great feature when crossing lakes if you out hiking, for instance, or if you are caught in the rain or a storm.

The eTrex is a popular GPS model from Garmin, displaying up to 500 waypoints and offering controls on the side to maximize the unit's display size. It is lightweight and waterproof.

For example, the Garmin eTrex Summit offers some great features, such as the built-in compass allowing you to stand in one place and still get a reading. This is handy since some GPS devices require movement in order to get a reading. This model has twelve channels like other GPS models, which gives you other options when nearby GPS devices may give cause some interference to you unit.

Ultimately, you definitely get what you pay for. Prices range from $100 to $300 and more. So, be sure to do some research, look at a wide variety of models and choose the GPS unit that has the features you will find most useful and beneficial during your travel and holiday trips. This is the best way to find a model that meets your needs and is within your budget.