A service is defined as an individual mechanism provided or maintained by the IT department to facilitate specific functions carried out by the end users. These should be named in simplistic terms so that they can be easily understood by all and could include examples such as Email, Intranet, or Printing.
Services are held and maintained within the Service Portfolio (Your Company > Service Portfolio):
From this point the services can be flagged as live in the catalogue so that calls can be logged against them, included in Service updates for end user visibility and maintained and supervised to enable the monitoring of the current operational status of a service as either one of Online, Offline or Impacted.
Learn more about this topic by visiting the Service Portfolio page.