Reflexive: all pairs are connected to themselves
Irreflexive: none of the pairs are connected to themselves
A relation can be Reflexive, Irreflexive, or neither (it’s not a this or that situation).
Same goes for Symmetric and Antisymmetric relations
Transitive: If you can go from a to b, and from b to c, then you should be able to go directly from a to c.
Partial Ordering: Transitive, Reflexive, and Antisymmetric
Ex: less than or equal to