A handheld GPS device offers the technology to navigate to exactly where you need to go and gives you the fastest way to get there. Never again will you wonder where you are.

You Will NeedReasons for using GPS
GPS device functions
Test units

Step 1: Consider GPS use（考慮一下你使用它的頻率和要求）
Consider how often you’ll use your unit and in what capacity. For occasional use, such as geocaching, you won’t need too many waypoints, or tracks, for your GPS. An avid hunter or fisherman, or someone who wants to mark spots along a set route will need a GPS unit with more storage and functions.

Geocaching is a treasure hunting, hide-and-seek game that uses GPS.

Step 2: Decide how advanced GPS should be（根據要求選擇不同質量的gps）
Decide how advanced your unit needs to be. Most every GPS can track waypoints so you can see where you have been. Less expensive units will backtrack manually. More advanced, and more expensive, devices have a trackback feature, which allows you follow your original route in reverse.

Some GPS units can be connected to your computer for map downloads.

Step 3: Select functions（選擇你需要的功能）
Select the functions you’ll need. Available features may include additional hardware for expanded memory; varying degrees of water resistance; fixed versus expandable memory; and varying levels of resolution and reception, battery size and life, and the unit’s weight.

Step 4: Consider system with multi-parellel channels（選擇多頻道的GPS系統）
Consider a system that has multi-parallel channels. The additional satellite signals can increase accuracy to nearly a pinpoint level. Such a receiver may increase the overall size of the unit.

Step 5: Test（買之前先測試一下）
Test the demonstration units set up in stores. Compare prices and models to find out which system you’re most comfortable with; a highly-specialized system will cost more than a multipurpose one.

Geocaching began on May 3, 2000, in Beaver Creek, Oregon, immediately after the government loosened satellite restrictions.