Related List Overview
The Related List appears in the Data View of a record once a record has been selected. These modules are related to the current record being viewed by the use of Reference Fields in Module Configuration.
Using the previous example the Task module is an option on the Contact Record because a Reference Field for the Contact module was mapped in the Task Module. That Reference Field is what makes the link from Task to Contacts.
For information on Field Mapping see /wiki/spaces/SMSAGV9/pages/212896.