Functions (F), which describe the aim of the object, i.e., what the object is for;
Structures (S), which describe the object’s components and their relationships, i.e., what the object is; and
Behaviours (B), which describe the attributes that are derived or expected to result from the structure (S) variables of the object, i.e., what the object does. These variables are created and transformed by processes, which take place in three diverse worlds that are recursively linked together.