The GMap module is primarily an API packaged with a few modules to give some functionality.
The API allows developers of other modules to include Google Maps in
their module. There is also a macro generator and a filter to insert a
google map from a macro into any node where the filter is run.
A second module packaged with gmap.module integrates with the
location.module and allows users that have lat,long information entered
for the user to be displayed on a single map so that you can see where
in the world all of your users are coming from. The gmap.module also
includes functionality to allow users to set their latitude and
longitude on a gmap in an interactive fashion.
This module also adds some functionality to location.module that can
allow the node locations to be set in an interactively. Then the
location of the current node can be shown in a block if it has lat/long
information stored for it in the location.module. All of the nodes that
have lat/long location information can be viewed on a common map.
The above description is for the Drupal 4.7 version. The 4.6 version
does not have the user functionality and the programming API is not as
complete.
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