The geometry service helps applications do geometric calculations such as buffering, simplifying, calculating areas and lengths, and projecting. Additionally, the ArcGIS Web APIs use the geometry service to create and modify feature geometries during web editing. The geometry service provides an alternative to doing these calculations using fine-grained ArcObjects or a geoprocessing service.
The geometry service is automatically created for you in the Utilities folder when you install ArcGIS for Server. It is only visible to publishers and administrators and can be configured through Manager, ArcCatalog, or the Catalog window in ArcGIS for Desktop. Also, publishers and administrators can see the geometry service and discover its REST URL using the Services Directory.
Those who make user connections to the server do not see the geometry service. However, they may be affected by the increased functionality that the geometry service provides through client applications developed with the ArcGIS Web APIs.
Administering the geometry service
By default, the geometry service is not started after you complete your installation ArcGIS for Server installation. Before you can use the geometry service to do geometric calculations, you'll need to start it in Manager or ArcGIS for Desktop. For full instructions, see the following topics:
Only one geometry service can exist in your ArcGIS server site. However, you can configure multiple instances of the service to run at the same time. You do this by increasing the Maximum number of instances property when configuring your geometry service in Manager or ArcGIS for Desktop. The topic links above contain instructions on how to access this property. For more information about pooling, see Tuning and configuring services.
If you want to move the geometry service from the Utilities folder to another folder on the server, you'll need to delete the service and re-create it using the ArcGIS Server Administrator Directory. See Re-creating the geometry service for full instructions.
Developing with the geometry service using the ArcGIS API for JavaScript
The ArcGIS API for JavaScript contains examples of how to consume the geometry service through code to create or make changes to feature geometries.