Tools used for synchronization
The following article briefly describes the Microsoft tools that current exist today for synchronization.
List of tools
Connect sync - Microsoft Entra Connect is an on-premises Microsoft application that's designed to meet and accomplish your hybrid identity goals. For more information, see What is Microsoft Entra Connect?.
Microsoft Identity Manager with the Graph connector - Microsoft's on-premises identity and access management solution that provides advanced inter-directory provisioning to achieve hybrid identity environments for Active Directory, Microsoft Entra ID, and other directories. For more information, see Microsoft Identity Manager. MIM is slowly being deprecated and should only be used in advanced scenarios. For more information, see Deprecated Features and planning for the future
Selecting the right tool
Each of these tools can accomplish similar results. So selecting the right tool is essential. Then connect sync and for advanced/complex scenarios, MIM. To determine which tool is right for you, you should use the wizard at the Choosing the right sync tool site.