When setting up relationships in your database it usually is the case that you would then like to see these relationships while viewing a record.  In what would be the child record (or the many in a one-to-many relationship) you have always been able to click on the arrow to go to the parent record but you can now see all the records linked to this entry on the record detail screen of the parent record.  One example of this would be in an Orders database where you have multiple Products associated with that order.  In this case you would view the order and automatically see all the products on that order. (see picture below).

From this view of the child records you can edit any of the records as well as create new records that are automatically linked to the original parent record.  Once you create a link between databases this will automatically appear in your parent database requiring no further setup on your end.  Using this and a join table you can build many-to-many relationships to create advanced applications