| 1 | Parent A code to indicate a parent relationship. |
| 2 | Child A code to indicate a child relationship. |
| 3 | Peer, internal A code to indicate an internal peer relationship. |
| 4 | Peer, external A code to indicate an external peer relationship. |
| 5 | Finish to start constraint A code to indicate a finish to start constraint relationship. |
| 6 | Start to start constraint A code to indicate a start to start constraint relationship. |
| 7 | Finish to finish constraint A code to indicate a finish to finish constraint relationship. |
| 8 | Start to finish constraint A code to indicate a start to finish constraint relationship. |
| 9 | Owner A code to indicate an owner relationship. |
| 10 | Contact A code to indicate a contact relationship. |
| 11 | Spouse A code to indicate a spouse relationship. |
| 12 | Sibling A code to indicate the relationship between brothers and/or sisters. |
| 13 | Father A code to indicate a father relationship. |
| 14 | Mother A code to indicate a mother relationship. |
| 15 | Neighbour A code to indicate a neighbour relationship. |
| 16 | Friend A code to indicate a friend relationship. |
| 17 | Guardian A code to indicate a guardian relationship. |
| 18 | Connecting to The specified object connects to the related object. |