Tuple report parameter
Many reports contain a number of filter dimensions. Users can change their view of the report data by selecting different elements from the filter dimensions.
When used in dashboards, the filter dimensions are often used in widget communication. For example, if a user selects a date in one report widget, the data in other widgets is updated to reflect that date.
If you create dynamic reports or self-service templates for use in dashboards, you will typically store the all the filter selections in a single XML variable.
See Using XML variables with filter dimensions.
But widget communication requires an individual variable for each selection. If you assign the XML variable to a Tuple report parameter, widget communication can extract the individual value from the variable and assign a parameter to each.