If you have the permission to administer markers, the option marker types (or the localized translation) will be available in the action bar on top of the maps tool.
It is not required to configure the marker types of the maps tool. If no types are configured, the default will be used. If only one type is configured, that type will automatically be used for all new markers. If there are multiple types configured, the option to select a type will be available to users.
The marker types can be defined using the list on the marker types administration page. A type can be created by entering a label in the type name box. New types can be added by clicking the plus (+) icon. Types can be ordered using the up an down arrows. The type color can be changed using the drop down box.
Marker types can be deleted, but only if the the type is not currently used in markers. The delete icon will only be available if there are no markers that use the type. Before deleting a marker type, you have to make sure that it is not in use. This can be done by either deleting the markers or changing the type for these existing markers.