A service is a check point, or indicator, to be monitored on a host, e.g.: percentage of partition used on a server, ink level in a printer.
To see the list of monitored services, go to Configuration > Services > Services by host.
Monitoring a service
Create a service:
Use the host autodiscovery feature: the corresponding services will be created automatically.
Use the service discovery feature.
Create a service using the API.