Area settings allow you to determine how the data will be processed for an entire data map. Not all mappings contain area settings, but you can identify those that do by the red or green radio button at the end of the row showing that mapping area within the template. Below, you can see mappings for each area that is available within the Event Participant destination. Two of these areas have area settings: Participant Attributes and Registration Fees.
Participant Attribute Area settings allow you to chose what constitutes a match for a participant attribute:
The Area Settings for the Participant Registration Fees allow you to determine what constitutes a matched fee record and how to handle matches.