When looking at a type you've created in schema editor you might see a header at the bottom the page that says Incoming Properties . This means that some other user thinks your type is so cool, they've linked to it from a property within one of their types. Maybe you've even linked to it yourself because you want to create a relationship between the type you're looking at and the property in the other type. The thing about incoming properties is that you can also create a return link to the incoming property so that the properties in both types can share information. Consider the following example.
Let's say that we have two types we want to create: Book and Author. Imagine that these types don't yet exist in the system. We create the type Book and add a property called Author with an expected data type of 'Author'. Remember that prior to adding this property, Author did not exist as a type. You've only just created it.
At this point you would probably expect to be able to add a book topic (Crime and Punishment ) and when editing this book topic, you should be able to add an author (Fyodor Dostoevsky ). This works just fine, in fact, but when you click on the link to view the author, you will find that there is no link back to the book you came from. This is because the link is not yet reciprocal -- it is an incoming link.
To make it reciprocal, you would need to add a property to the type for Author that you just created. When looking at your Author type in Schema Editor, you would see, at the bottom of the page, under Incoming Properties , the name of the type containing the incoming property (Book), the name of the incoming property (Author), and its description. To create the reciprocal link you would click Create a return link (this is all covered in more detail in Using Schema Editor to Create New Types )
That's it. If you returned to the page for this author, you would now see the book he wrote listed under 'Books'. You can now navigate back and forth through the reciprocal link you created from Author (FD) to Book (C&P) and back again.
