Overview of profile
synchronization in SharePoint Server 2013
A user profile is a collection of
properties that describes a SharePoint user. Features such as My Sites and
People Search use user profiles to provide a rich, personalized experience for
the users in your organization. You can create user profiles by importing data
from directory services, such as Active Directory Domain Services (AD DS).
You can augment user profiles by importing data from business systems, such as
SAP or SQL Server. The process of importing profile data from external systems
and writing data back to these systems is called profile synchronization.
Please find the below link from
MS:
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