An asymmetric relation is a type of binary relation that requiers:
Antisymmetry is different from asymmetry because it does not requier irreflexivity, therefore every asymmetric relation is antisymmetric, but the reverse is false.
A relation that is not asymmetric, is symmetric.
A asymmetric relation is an directed relationship .
It's also known as a uni-directional relationship.
When there is a direction on the association, the relationship is asymmetric.
A asymmetric relation in the set of {1,2,3} would be the set of tuple
<1,3>
<2,1>
<3,2>