Synchronization makes sure any changes to a file on the desktop or in OneDrive (personal) are reconciled so that each copy of the file remains the same.
Sync files to your computer
This part is easy. OneDrive (personal) automatically syncs whenever you sign in.
You can also sync shared folders on Windows 10 and Windows 7. If you're running Windows 8.1, upgrade to Windows 10 for free.
For more information on OneDrive (personal), see OneDrive Help.
For more information about managing synced files on your desktop, see OneDrive desktop app for Windows: FAQ.