Basics:

        Before you purchase a GPS there are six basic things you need to consider.

• What is a GPS?
  A GPS unit is a electronic device that can determine your approximate location (within around 6-20 feet or 3 to 9 meters) on the planet. Coordinates are normally given in Longitude and Latitude. You can use the unit to navigate from your current location to another location. Some units have their own maps, built-in electronic compasses, voice navigation, depending on the complexity of the device.
  There is NO Fee for using a normal GPS!
   
• How dose a GPS work?
  If you're interested in finding more information about Global Positioning Systems, check out GPS: The New Navigation by PBS. They have an excellent Shockwave and/or web page that explains how GPS works
   
• What is GEOCACHING?
  Geocaching is an entertaining adventure game for GPS users. Participating in a cache hunt is a good way to take advantage of the wonderful features and capability of a GPS unit. The basic idea is to have individuals and organizations set up caches all over the world and share the locations of these caches on the internet. GPS users can then use the location coordinates to find the caches. Once found, a cache may provide the visitor with a wide variety of rewards. All the visitor is asked to do is if they get something they should try to leave something for the cache. For more info please click HERE.
   
• What is DATUM?
  A datum is something used as a basis for calculating and measuring. In the case of GPS, datums are different calculations for determining longitude and latitude for a given location.
  Currently, Geocaching, most new maps and GPS devices use the WGS84 datum for all intensive purposes. Many maps still use NAD27, which can cause confusion if your GPS unit is set to NAD27. Always check your GPS to ensure that WGS84 is the datum before entering a waypoint coordinate into your unit.
   
• Why do I need to be aware of what WGS84 is?
  The most current geodetic datum used for GPS is the World Geodetic System of 1984 (WGS84). The significance of WGS84 comes about because GPS receivers rely on WGS84.
  
  It is critical that the datum format is correct, otherwise waypoints shared or received may conflict and point you to an incorrect location.
   
• What is WAAS?
  WAAS stands for Wide Area Augmentation System, but that doesn't really describe what it is. Garmin has an excellent description on WAAS.
   
• Is there any dead zones?
  YES there are.
  As with any portable device, like a cell phone for example. There are areas where hills, thick foliage and brick walls from tall buildings will block signal reception. This is a fact of life but can be over come by finding a clear view of the sky.
   

The Best GPS for me:

        When considering a GPS let me first share some advice. Ask your self the following questions and write the answers down in a list format. Take your answers and find a GPS that fills the bill.

• What is it I intend to accomplish with a GPS?
  Am I going to use it primarily for point to point navigation or am I going to use it for a sport like Geocaching?
   
• What is the minimum I need it to do in order to {answer from question 1}?
  Find your minimum so when you compare the different models you will be able to make an educated decision about other options available.
   
• What is its accuracy?
  The best accuracy allowed by law is about 3 meters or 9 feet. The better units will accomplish this. I would suggest selecting a device capable of tracking 12 satellites simultaneously as well as having WAAS and averaging capabilities.
   
• What is the battery life of the device?
  This totally depends on the model you chose. If it has a color display then the battery life will be lower because of the backlight needed to show the colors. Also some of the added features will require more power depending on the model.
   
• Is it easy to read?
  You need to make sure you can read the display. If you can't read and understand what is displayed then it will be of no use to you. Make sure before purchasing any GPS device that you are comfortable reading and navigating around the various screens and menus.
   
• Is there a difference in the antennas from one device to another?
  YES there is.
  Recently there has been an advancement in this area for handheld GPS devices. A Quad Helix Antenna was introduced in the newer higher end models. The difference is that instead of one antenna with a larger surface area you now have four individual antennas detecting signal. These new antennas provide for some seriously improved reception.
   

Comparison:

          I will share my personally preferences with you. I currently own and have used plenty of different GPS devices. I prefer to use GARMIN over MAGELLAN out of personal preference. I have gotten used to the menus and have software for that particular brand.