Waypoint
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A waypoint is a fixed location with a specified longitude and latitude and UTM coordinates, which is maintained by a global positioning system (GPS). Waypoints mark a destination, a point along the way to a destination, or a point of reference. GPSs can record a waypoint on the spot to within 3 meters or better using a WAAS enabled GPS unit. Waypoints can also be marked on a computer mapping program and uploaded to the GPS, marked on the GPS's own internal map, or entered manually on the device as a pair of coordinates.
In navigating with a GPS, a "route" normally consists of one or more waypoints. To traverse a route, the GPS user navigates to the nearest waypoint, then to the next one in turn until the destination is reached. Most units have the ability to compute a great-circle route towards a waypoint, enabling them to find the shortest route even over long distances.
Many GPS units, both military and civilian, now offer integrated cartographic databases, enabling users to locate a destination on a map and define it as a waypoint. Some GPS systems intended for automobile naviagion can generate a suggested driving route between two waypoints, based on the cartographic database. As one drives along the route, the system indicates the driver's current location and gives advance notice of upcoming turns.
Most GPS units allow the user to assign a name to each waypoint. Many models also let the user select a symbol to identify the waypoint on a graphical map display from a built-in library of icons. These include standard map symbols for marine navigation aids such as buoys, as well as such land-based symbols as churches, bridges, shopping centers, parks, and tunnels.