Affiliation Mappings are used to automatically create and populate the Primary Affiliation field on the Contact record based on the Account record type of the related Affiliation. For example, if a Contact has an Affiliation with an Account of record type "Academic Program", the Primary Affiliation field on the Contact record will be populated with that Account name. The consultant can go to Affiliation Mappings in EDA Settings to configure which Account record types should trigger this behavior and which fields should be used to store the Primary Affiliation. Reference:
Education Data Architecture Basics - Unit 3: Affiliations and Relationships EDA Documentation - Affiliation Mappings