All of the programmatic linkage references are in the fields "Parent ID", "Self ID", "Child IDs", "Parent Stack Name", and "Child Stack Name". The fields "Self Name" and "Parent Name" are for user dispaly reference and reporting. The numbers in the linkage fields are the HyperCard card IDs, assigned by HyperCard when the card is created. We are assured that those IDs are unique within a stack, and HyperArchy always refers to a card (internally) as
"card ID ... of stack ...".
The purpose of the contents of each linkage field should be apparent from the field's name. Note that "Child IDs" is a list of ID numbers, with the oldest child first, new childern added to the end, and deleted children removed from the list as appropriate.
There is no peer-to-peer linkage. Peers can be grouped by using the "Sort: Parent" button.