Types of Knowledge Applications
You can set up users to use Knowledge in Service Center, Help Desk, Fusion Service, and HCM HR Help Desk applications.
In some cases, you may have users who contribute or use knowledge in more than one application. It's important to keep the application in mind as you set up users, because users must have privileges in at least one application. Additionally, most of the predefined knowledge roles support only one application.
Note:
Applications are also called departments in the user roles pages and in some other contexts.