The User Profile service is used by SharePoint Server to store data about users. It's required for My Sites and OneDrive, social networking features such as tagging and newsfeeds, creating and managing audiences and organizational charts, and delivering user profile information to other services or web applications (either on the local farm or connected farms). The User Profile service is also used by servers for accessing resources on behalf of users in server-to-server authentication scenarios, as well as in SharePoint Hybrid scenarios.
The User Profile Service has a dependency on the Managed Metadata service application (you'll learn how to configure the Managed Metadata service in Chapter 7, Planning and Configuring Managed Metadata), as well as My Site collections.
In this section, we'll look at an overview of some of the planning tasks for the User Profile service before configuring the User Profile service application.