This is another example of terms often used interchangeably. However, ITIL clarifies that the Service Catalog lists only live IT services but Service Portfolio is a bigger set including services in the pipeline and retired services as well. Service Catalog contains information about two types of IT services:
ServiceDesk Plus plays a vital role in managing the ways in which these services are exposed to users. The software provides a simple and effective interface to browse through the services and monitor their status. Users can also request for availing these services from within the module.
The Service Catalog can also be accessed from the Admin tab, by clicking on Service Catalog under the Helpdesk block. The page lists the configured service categories and can be used to Add Service Category, Manage the service items, and Add Service under each category.
Deletion of an existing Service Category should be done with care. Here are the steps:
Select Service Categories from Manage dropdown.
A window with Service Categories List will open.
Select the check box next to the Service Category to be deleted and then press the Delete button on the interface.
A confirmation box will appear and on confirmation, the Service Category will be processed for deletion.
Note
If the concerned Service Category is in use by a module, then it will be grayed out and the category will be unavailable for further usage. To bring it back into usage, click on the edit icon 
next to the category name and uncheck the box for Service not for further usage in the new window.
The following two options under the Manage dropdown provide additional features for the customization of service request forms: