Synchronization determines whether the visualization should interact with other elements on the same Dashboard:
Row Filtering - When checked, this causes the Visualization to use the categorical and numeric filters on the Dashboard.
Time Filtering - When checked, this causes the Visualization to use any time filters on the Dashboard.
Selection - When checked, items selected in another Visualization will also be selected on this Visualization.
Focus - When checked, when focus is set on another Visualization the system will also set focus on this Visualization.
You can also enable the Shared or Visible options of the visualization’s variables. Refer to Synchronization of the Shared and Visible Variables in the Visualizations of a Dashboard for more information.